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Time Value of Money - Present Value vs Future Value

The Organic Chemistry Tutor · YouTube · 5:14

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This introductory lesson explains the core concepts of present value and future value within the time value of money framework. Using a whiteboard format, the instructor defines these terms and presents a practical example: calculating the future value of $10,000 over 20 years at a 6% annual interest rate. The video derives the solution using the standard compound interest formula, FV = PV(1+r1+r)^n, arriving at approximately $32,071.35. It concludes by illustrating why money today is worth more than the same amount in the future through a relatable example of changing purchasing power. This 150-second whiteboard segment teaches present value through a worked finance example. It first uses a chips analogy to show that purchasing power falls over time, then introduces the rearranged formula PV = FV/(1+r1+r)^n. The speaker applies it to find the present value of $100,000 received 10 years from now at 6% annual interest, obtaining $55,839.48. The clip closes by interpreting that result as the amount with the same purchasing power as $100,000 ten years later under 6% inflation, summarizing the time value of money. This short whiteboard segment introduces the time value of money through present value and future value examples. The board already shows two numerical cases at 6% annual interest: $10,000 growing to $32,071.35 in 20 years, and $100,000 received in 10 years having present value $55,839.48. A third row compares $1000 now with $1000 in the future, and the speaker emphasizes that the present amount has more purchasing power. The formula PV = FV / (1+r1+r)^n is written on the board and applied to the $100,000 example.

Use the learning inspector for key ideas and moments, or open the reading tabs for the complete notes.

Chapters

0:00Introduction to Present and Future Value0:19Example Problem Setup0:56Future Value Formula and Calculation1:58Understanding the Time Value of Money2:30Purchasing power analogy3:03Second part of the problem: present value setup3:40Rearranged formula and substitution4:18Interpretation: time value of money5:00PV vs FV board setup and $1000 comparison5:08Statement of the time value of money principle

Learning script

Generated from the video's visuals and explanation; not verbatim speech.

The video opens by defining the fundamental concepts of finance: present value (the worth of money today) and future value (its worth at a later date). This establishes the framework for understanding how money grows over time.

To demonstrate these concepts, a specific problem is introduced: finding the future value of $10,000 invested for 20 years at a 6% annual interest rate. A simple timeline diagram is drawn to visually organize the given information—present value, time, and interest rate—and identify the unknown future value.

The mathematical tool for solving this is the compound interest formula, FV = PV(1+r1+r)^n. The instructor substitutes the problem's values into the equation: FV = 10,000(1+0.06)20000(1+0.06)^20. After simplifying the base to 1.06, the calculation yields a future value of approximately $32,071.35.

Finally, the lesson connects the numerical result back to economic reality. It explains that receiving $10,000 today is preferable to receiving it in 20 years because of its higher purchasing power. A relatable example compares the cost of a bag of chips today versus twenty years ago, illustrating how inflation erodes the real value of money over time.

The clip opens on a black digital whiteboard with the earlier future-value problem still visible: $10,000 grows to $32,071.35 over 20 years at 6%, and the formula FV = PV(1+r1+r)^n is already written below. Over this, the instructor adds a simple purchasing-power comparison, writing $1→41 \to 4 bags and $1→11 \to 1 bag. The spoken example is slightly inconsistent in its time wording, but the mathematical point is clear: the same nominal dollar buys fewer goods later, so real purchasing power declines as time moves forward.

The instructor then turns to the second part of the problem, asking for the present value of $100,000 ten years from now at the same 6% annual interest rate. On the board, $100,000 is placed under the FV label, and the horizon is marked as 10 years with the same 6% rate. This reframes the situation: instead of compounding a present amount forward, the task is to discount a known future amount backward to today.

To do that, the video explicitly rearranges the compound-interest relationship. The general formula shown is PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}, where FVFV is the future amount, rr is the annual rate as a decimal, and nn is the number of years. The instructor substitutes the given values step by step: PV=100,000(1+0.06)10PV = \frac{100{,}000}{(1+0.06)^{10}}, then simplifies the base to get PV=100,000(1.06)10PV = \frac{100{,}000}{(1.06)^{10}}, and finally evaluates the quotient to obtain PV=55,839.48PV = 55{,}839.48.

With the numerical answer on screen, the clip shifts from calculation to interpretation. The instructor says that if inflation is also 6%, then $55,839.48 today has the same purchasing power as $100,000 ten years later. This is the key conceptual bridge: the discounted present value is not just a formula output, but the amount that makes a present sum and a future sum economically comparable. The segment closes by stating the general principle of the time value of money: the same amount of money is worth more now than it will be worth in the future.

The clip opens on a completed whiteboard problem about present value and future value. At the top, the written prompts ask for the future value of $10,000 twenty years from now at 6% annual interest and the present value of $100,000 ten years from now at the same rate. The left column is labeled PV and the right column is labeled FV, with arrows running left to right to show movement through time.

While the speaker says that the thousand dollars in the present has more purchasing power than the thousand dollars in the future, a red box is drawn around the left $1000 in the third row. That visual emphasis marks the present-dollar amount as the economically stronger one, even though the right side also shows $1000.

The speaker then states the general principle behind the whole board: money is worth more now than it is in the future. This verbal summary matches the structure of the examples above, where equal nominal amounts are not treated as equal in value across time.

The bottom of the board supplies the quantitative rule for that idea: PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}. The symbols are used consistently across the examples: PVPV is present value, FVFV is future value, rr is the annual rate, and nn is the number of years.

The worked examples show how the formula is applied. In the first case, 10,00010,000 at 6%6\% for 2020 years becomes 32,071.3532,071.35 in the future. In the second case, the board substitutes into the formula as 100,000(1.06)10\frac{100,000}{(1.06)^{10}}, and the displayed present-value result is 55,839.4855,839.48. The clip ends with the conceptual point still foregrounded: discounting and compounding are the arithmetic expressions of the time value of money.

Knowledge cards

01

Time Value of Money: Present vs. Future Value

Present value (PV) is the current worth of a sum of money, while future value (FV) is what that sum will be worth at a later date after earning interest. Understanding this distinction is crucial because money available now can be invested to grow, making it more valuable than the same nominal amount in the future.

02

Future Value Formula

The future value of a lump sum is calculated using the compound interest formula: FV = PV(1+r1+r)^n. In this equation, PV is the initial principal balance, r is the interest rate per period, and n is the number of compounding periods. This formula shows how an investment grows exponentially over time.

FV=PV(1+r)nFV = PV(1+r)^n
03

Calculating Future Value (Example)

To find the future value of $10,000 after 20 years at a 6% annual interest rate, substitute the values into the formula: FV = 10,000∗(1+0.06)20000 * (1 + 0.06)^20. Simplifying gives FV = 10,000∗(1.06)20000 * (1.06)^20. Evaluating this expression results in a future value of approximately $32,071.35.

FV=10,000(1.06)20≈32,071.35FV = 10,000(1.06)^{20} \approx 32,071.35
04

Purchasing Power and Inflation

The time value of money is closely tied to purchasing power. Due to inflation, a dollar today generally buys more goods and services than a dollar will in the future. For example, if a bag of chips costs $1.00 now but cost $0.25 twenty years ago, the real value of the dollar has decreased, highlighting why future sums must be discounted to compare fairly with present sums.

05

Purchasing power falls over time

The opening example compares what one dollar can buy at different times, using bags of chips as a concrete good. The board writes $1→41 \to 4 bags and $1→11 \to 1 bag, showing that the same nominal dollar purchases less later. This motivates discounting future cash flows because a future dollar is not equivalent in real value to a present dollar.

06

Future-value formula retained on the board

Before solving the second part, the earlier relation FV=PV(1+r)nFV = PV(1+r)^n remains visible from the first example. It serves as the starting point for the next step: if you know the future amount and want today’s equivalent, you must solve the same relationship for PVPV.

FV=PV(1+r)nFV = PV(1+r)^n
07

Present-value formula

The video rearranges the compound-interest equation to isolate present value: PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}. Here FVFV is the known future amount, rr is the annual interest rate expressed as a decimal, and nn is the number of years. This formula converts a future sum into its equivalent amount today under the given rate.

PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}
08

Worked example: PV of $100,000 in 10 years at 6%

The instructor applies the formula to the specific data FV=100,000FV = 100{,}000, r=0.06r = 0.06, and n=10n = 10. The substitution is PV=100,000(1+0.06)10=100,000(1.06)10PV = \frac{100{,}000}{(1+0.06)^{10}} = \frac{100{,}000}{(1.06)^{10}}, which evaluates to 55,839.4855{,}839.48. Thus, $100,000 received ten years from now is worth $55,839.48 today at a 6% annual rate.

PV=100,000(1.06)10=55,839.48PV = \frac{100{,}000}{(1.06)^{10}} = 55{,}839.48
09

Equivalent purchasing power under 6% inflation

After computing the present value, the speaker interprets the result economically: if inflation averages 6% per year, then $55,839.48 today has the same purchasing power as $100,000 ten years later. This links the algebraic discount factor to the real-world idea that rising prices reduce the future buying power of money.

10

Time value of money conclusion

The closing takeaway is that the same nominal amount of money is worth more now than in the future. The worked PV calculation illustrates why: positive rates imply that future cash must be discounted to compare fairly with cash available today.

11

Time value of money: money is worth more now

The video states the central principle directly: money available today is worth more than the same nominal amount in the future. This is illustrated by comparing $1000 now with $1000 later, where the speaker says the present amount has more purchasing power.

12

Present value formula

The board gives the discounting relation PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}. Here FVFV is the future amount, rr is the periodic interest or discount rate, and nn is the number of periods. The example on the board applies it with FV=100,000FV = 100{,}000, r=0.06r = 0.06, and n=10n = 10.

PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}
13

Example: future value of $10,000 after 20 years at 6%

The first worked example shows $10,000 on the PV side growing over 20 years at 6% to $32,071.35 on the FV side. The clip presents the result visually rather than deriving it step by step.

10,000→6%20 yrs32,071.3510{,}000 \xrightarrow[6\%]{20\text{ yrs}} 32{,}071.35
14

Example: present value of $100,000 received in 10 years at 6%

The second example asks for the present value of 100,000tenyearsfromnowat6100,000 ten years from now at 6%. The board writes the substitution 100,000(1.06)10\frac{100,000}{(1.06)^{10}}anddisplaystheresult and displays the result 55,839.48$ on the PV side.

PV=100,000(1.06)10=55,839.48PV = \frac{100{,}000}{(1.06)^{10}} = 55{,}839.48
15

Equal nominal amounts are not equal economic amounts

A common mistake is to treat $1000 today and $1000 in the future as equivalent just because the numbers match. The video explicitly rejects that by highlighting the present $1000 and saying it has more purchasing power than the future $1000.

Detailed learning notes

Explore conditions, steps and evidence. Supplementary explanations are labeled separately from content shown in the video.

Symbols · 14

PV

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says, "So right now in the present we have ten thousand dollars. So that's the present value."

  2. Formula
    Observation

    The handwritten label "PV" is written above "$10,000".

  3. Formula
    Observation

    The formula "FV = PV(1+r1+r)^n" is written on the screen.

Symbol

PV

Meaning

Present value, representing the value of money today.

Domain

Monetary amount (dollars).

FV

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says, "So we're looking for the future value."

  2. Formula
    Observation

    The handwritten label "FV" is written at the end of the arrow.

  3. Formula
    Observation

    The formula "FV = PV(1+r1+r)^n" is written on the screen.

Symbol

FV

Meaning

Future value, representing the value of money at a specified time in the future.

Domain

Monetary amount (dollars).

r

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says, "The interest rate is six percent or point zero six."

  2. Formula
    Observation

    The variable "r" is used in the formula "FV = PV(1+r1+r)^n" and substituted with "0.06".

Symbol

r

Meaning

Annual interest rate.

Domain

Decimal fraction (e.g., 0.06 for 6%).

n

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says, "n is the number of time periods... which is twenty years."

  2. Formula
    Observation

    The variable "n" is used as the exponent in the formula "FV = PV(1+r1+r)^n" and substituted with "20".

Symbol

n

Meaning

Number of compounding periods (years in this context).

Domain

Positive integer.

PV

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    PV is written in the problem statement and used as the left-hand side of the present-value formula.

  2. Audio
    Observation

    The speaker refers to “present value” while setting up the second part of the problem.

Symbol

PV

Meaning

Present value, the current worth of a future amount discounted at rate r over n periods.

Domain

Monetary amount; in this example dollars.

FV

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    FV is written in the problem statement and used as the numerator in the rearranged formula.

  2. Audio
    Observation

    The speaker says “we’re given the future value, which is $100,000.”

Symbol

FV

Meaning

Future value, the amount at a later date that is being discounted back to the present.

Domain

Monetary amount; in this example dollars.

r

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    r appears in FV = PV(1+r1+r)^n and in PV = FV/(1+r1+r)^n.

  2. Audio
    Observation

    The speaker states that r is still 0.06 for the 6% annual interest rate.

Symbol

r

Meaning

Annual interest rate expressed as a decimal.

Domain

Rate per period; here r=0.06r = 0.06.

n

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    n appears as the exponent in both formulas.

  2. Audio
    Observation

    The speaker says “and n is 10” when substituting into the present-value formula.

Symbol

n

Meaning

Number of compounding periods (years).

Domain

Positive integer count of years; here n=10n = 10 for the second part.

$100,000

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    $100,000 is written under the FV label and substituted into the numerator of the PV formula.

  2. Audio
    Observation

    The speaker identifies $100,000 as the future value in the second part of the problem.

Symbol

$100,000

Meaning

Given future amount to be discounted back 10 years.

Domain

Dollar amount.

$55,839.48

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    $55,839.48 is written as the result of the present-value calculation.

  2. Audio
    Observation

    The speaker reads the answer as fifty-five thousand eight hundred thirty-nine dollars and forty-eight cents.

Symbol

$55,839.48

Meaning

Computed present value of $100,000 received 10 years from now at 6% annual interest.

Domain

Dollar amount.

PV

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board shows the label PV and the formula PV = FV / (1+r1+r)^n.

  2. Audio
    Observation

    The speaker discusses present value in words while the PV label is visible.

Symbol

PV

Meaning

Present value; the current worth of a future amount discounted at rate r over n periods.

Domain

Monetary value, typically dollars.

FV

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board shows the label FV and the numerator FV in PV = FV / (1+r1+r)^n.

  2. Audio
    Observation

    The speaker contrasts present value with future value.

Symbol

FV

Meaning

Future value; the amount an investment grows to after n periods at rate r.

Domain

Monetary value, typically dollars.

Knowledge points · 8

Time Value of Money Concepts

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker states, "The present value of money represents the value of money today, right now, in the present. Whereas the future value represents the value of that money in the future."

Definition
Explanation

Present value (PV) is the current worth of a sum of money, while future value (FV) is the worth of that same sum at a later date, assuming it earns interest over time.

Formula
Conditions
  1. Applies to monetary amounts subject to interest rates over time.

Future Value Formula

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says, "The formula that we could use to calculate the future value from the present value is this formula: FV is equal to PV times one plus r raised to the n."

  2. Formula
    Observation

    The equation "FV = PV(1+r1+r)^n" is written on the screen.

Formula
Explanation

This formula calculates the future value of a present sum using compound interest. It multiplies the present value by the growth factor (1+r)(1+r) raised to the power of the number of periods nn.

Formula
FV=PV(1+r)nFV = PV(1+r)^n
Conditions
  1. Assumes annual compounding when rr is an annual rate and nn is in years.

  2. Interest rate rr remains constant over the period.

Prerequisites
  1. Time Value of Money Concepts

Present value formula

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board shows PV = FV / (1+r1+r)^n.

  2. Audio
    Observation

    The speaker says the formula needs to be rearranged and states: “The present value is equal to the future value divided by one plus r raised to the n.”

Formula
Explanation

The video uses the rearranged compound-interest relation to compute today’s equivalent of a future amount. The denominator (1+r)n(1+r)^n discounts the future value back over nn periods at rate rr.

Formula
PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}
Conditions
  1. FV is known.

  2. r is the periodic interest rate expressed as a decimal.

  3. n is the number of periods.

Prerequisites
  1. Future value formula already shown on board

Future value formula already shown on board

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The earlier worked setup on the board includes FV = PV(1+r1+r)^n and the substitution 10,000(1+0.06)20=10000(1+0.06)^20 = 10,000(1.06)20000(1.06)^20.

  2. Audio
    Observation

    The speaker transitions from the first part of the problem to the second part, indicating the same interest-rate framework continues.

Formula
Explanation

Before solving for present value, the board retains the standard future-value relation FV=PV(1+r)nFV = PV(1+r)^n, which is then algebraically rearranged to isolate PVPV.

Formula
FV=PV(1+r)nFV = PV(1+r)^n
Conditions
  1. PV is known.

  2. r is the periodic interest rate expressed as a decimal.

  3. n is the number of periods.

Time value of money interpretation

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker concludes: “this really illustrates the time value of money, and that is the same amount of money is worth more now than it will be worth in the future.”

  2. Diagram
    Observation

    The board contrasts $55,839.48 today with $100,000 ten years later.

Definition
Explanation

The clip defines the practical meaning of the calculation: a dollar today has greater purchasing power than the same nominal dollar in the future, so a future sum is worth less in present terms.

Conditions
  1. Comparison is made across different points in time using the same discount/interest rate.

Prerequisites
  1. Present value formula
  2. Purchasing power declines over time

Purchasing power declines over time

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says, “So twenty years in the past, one dollar can buy you four bags of chips. In the present, a dollar can buy you one bag of chips.”

  2. Diagram
    Observation

    The board writes $1→41 \to 4 bags and $1→11 \to 1 bag.

Uncertainties
  1. The spoken phrase “twenty years in the past” conflicts with the surrounding explanation about future purchasing power; the intended contrast is between an earlier time and the present/future direction of declining buying power.

Definition
Explanation

The chips example illustrates that the same nominal amount buys fewer goods later, motivating why future cash flows must be discounted to compare them with present cash.

Conditions
  1. Assumes prices rise over time or real purchasing power falls.

Basic idea of the time value of money

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    Speaker says: 'So the basic idea behind the time value of money is that money is worth more now than it is in the future.'

Definition
Explanation

The video states the core principle of the time value of money: a given amount of money is worth more today than the same nominal amount in the future. This is presented verbally while the board already contains PV/FV examples and the discounting formula.

Conditions
  1. Applies when comparing monetary amounts at different points in time under positive interest or discount rates.

Present value formula

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    Bottom-left board text reads: PV = FV / (1+r1+r)^n = $100,000/(1.06)10000 / (1.06)^10.

Formula
Explanation

The board gives the present-value relation PV = FV / (1+r1+r)^n and applies it to a future amount of $100,000 with r=6r = 6% and n=10n = 10 years. The formula expresses how a future sum is discounted back to the present by dividing by the growth factor (1+r1+r)^n.

Conditions
  1. PV is the present value.

  2. FV is the future value.

  3. r is the periodic interest or discount rate.

  4. n is the number of periods.

  5. The displayed application uses annual compounding with r=0.06r = 0.06 and n=10n = 10.

Prerequisites
  1. PV
  2. FV
  3. r
  4. n
Claims and conditions · 2

Equivalent purchasing power under 6% inflation

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says that if inflation is 6%, then $55,839.48 has the same purchasing power as $100,000 ten years later.

  2. Formula
    Observation

    This follows from the computed PV relation 55,839.48(1.06)10=100,00055,839.48(1.06)^{10}=100,000 implied by the displayed calculation.

Uncertainties
  1. The video verbally equates the interest rate with inflation for interpretation; it does not separately derive an inflation model.

Proposition
Statement

At a 6% annual inflation rate, $55,839.48 today has the same purchasing power as $100,000 ten years from now.

Hypotheses
  1. Inflation is 6% per year.

  2. The comparison spans 10 years.

  3. Discounting uses the same annual rate as inflation.

Quantifiers

For the specific amounts and horizon stated in the example.

Present dollars exceed future dollars in value

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker explicitly states: “the same amount of money is worth more now than it will be worth in the future.”

Proposition
Statement

The same nominal amount of money is worth more now than it will be worth in the future.

Hypotheses
  1. There is positive time value of money, represented here by a positive annual rate.

Quantifiers

General conclusion drawn from the worked example.

Derivations and proofs · 4

Calculation of Future Value

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker verbally substitutes the values: "So the present value is ten thousand... interest rate is six percent or point zero six... n is... twenty years. So it's going to be ten thousand times one point zero six raised to the twentieth power."

  2. Formula
    Observation

    The step-by-step calculation is written: "= 10,000(1+0.06)20000(1+0.06)^20", then "= 10,000(1.06)20000(1.06)^20", and finally the result "$32,071.35" is written next to the FV label.

Numerical verification
Steps
  1. Expression
    FV=10,000(1+0.06)20FV = 10,000(1+0.06)^{20}
    Explanation

    Substitute the given values into the future value formula: PV = 10,000, r=0.06r = 0.06, n=20n = 20.

    Justification

    Direct application of the formula FV = PV(1+r1+r)^n with the problem's specific parameters.

    Shown in the video
  2. Expression
    FV=10,000(1.06)20FV = 10,000(1.06)^{20}
    Explanation

    Simplify the term inside the parentheses by adding 1 and 0.06.

    Justification

    Basic arithmetic simplification.

    Shown in the video
  3. Expression
    FV≈32,071.35FV \approx 32,071.35
    Explanation

    Calculate the final value using a calculator.

    Justification

    Numerical evaluation of the expression 10,000∗(1.06)20000 * (1.06)^20.

    Shown in the video
Conclusion

The future value of $10,000 after 20 years at a 6% annual interest rate is approximately $32,071.35.

Substitution into the present-value formula

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board shows PV = FV/(1+r1+r)^n, then substitutes $100,000, 1.06, and exponent 10, yielding $55,839.48.

  2. Audio
    Observation

    The speaker narrates each substitution: future value is 100,000; r is 0.06 so 1+r1+r is 1.06; n is 10.

Numerical verification
Steps
  1. Expression
    PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}
    Explanation

    Start from the rearranged compound-interest formula shown on the board.

    Justification

    Algebraic rearrangement of FV = PV(1+r1+r)^n.

    Shown in the video
  2. Expression
    PV=100,000(1+0.06)10PV = \frac{100{,}000}{(1+0.06)^{10}}
    Explanation

    Insert the given future value, annual rate, and number of years.

    Justification

    Problem data: FV = $100,000, r=0.06r = 0.06, n=10n = 10.

    Shown in the video
  3. Expression
    PV=100,000(1.06)10PV = \frac{100{,}000}{(1.06)^{10}}
    Explanation

    Simplify the base of the denominator.

    Justification

    Arithmetic: 1+0.06=1.061 + 0.06 = 1.06.

    Shown in the video
  4. Expression
    PV=55,839.48PV = 55{,}839.48
    Explanation

    Evaluate the quotient to obtain the present value.

    Justification

    Numerical computation of 100,000/(1.06)10100,000/(1.06)^{10}.

    Shown in the video
Conclusion

The present value of $100,000 received 10 years from now at 6% annual interest is $55,839.48.

Intuitive explanation of discounting

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker compares what one dollar buys in the past versus the present/future using bags of chips.

  2. Diagram
    Observation

    The board writes $1→41 \to 4 bags and $1→11 \to 1 bag.

Uncertainties
  1. The exact temporal wording in the audio is inconsistent, but the mathematical point is the decline of purchasing power over time.

Intuitive argument
Steps
  1. Explanation

    Earlier, one dollar could buy four bags of chips.

    Justification

    Illustrative purchasing-power comparison stated in the audio and written on the board.

    Shown in the video
  2. Explanation

    Later, the same dollar buys only one bag.

    Justification

    Illustrative purchasing-power comparison stated in the audio and written on the board.

    Shown in the video
  3. Expression
    Purchasing power decreases over time\text{Purchasing power decreases over time}
    Explanation

    Therefore a future dollar is worth less in real terms than a present dollar.

    Justification

    Direct interpretation of the two comparisons.

    Derived from the video
Conclusion

The chips example motivates why future cash amounts must be discounted to compare them with present cash.

Substitution into the present value formula

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board writes PV = FV / (1+r1+r)^n and then the substituted expression $100,000/(1.06)10000 / (1.06)^10.

Uncertainties
  1. The final numerical value of $100,000/(1.06)10000 / (1.06)^10 is not written on the board in this clip.

Visual argument
Steps
  1. Expression
    PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}
    Explanation

    Start from the general present-value formula shown on the board.

    Justification

    Directly observed formula on the whiteboard.

    Shown in the video
  2. Expression
    PV=100,000(1.06)10PV = \frac{100{,}000}{(1.06)^{10}}
    Explanation

    Substitute FV = 100,000, r=0.06r = 0.06, and n=10n = 10 into the formula.

    Justification

    Matches the second worked example on the board, which asks for the present value of $100,000 ten years from now at 6%.

    Shown in the video
Conclusion

The clip shows the setup for computing the present value of $100,000 received 10 years from now at 6% annual interest, but does not display the final evaluated number.

Worked examples · 5

Future Value Example Problem

Clear evidence
Shown in the video
Evidence
  1. Caption evidence
    Observation

    The text on screen reads: "1. What is the future value of $10,000 twenty years from now given an annual interest rate of 6%?"

  2. Audio
    Observation

    The speaker reads the first part of the problem and proceeds to solve it.

Problem

What is the future value of $10,000 twenty years from now given an annual interest rate of 6%?

Given
  1. Present Value (PV) = $10,000

  2. Time period (n) = 20 years

  3. Annual interest rate (r) = 6% or 0.06

Goal

Calculate the Future Value (FV).

Steps
  1. Expression
    FV=PV(1+r)nFV = PV(1+r)^n
    Explanation

    Identify and write down the appropriate formula for calculating future value with compound interest.

    Justification

    Standard financial mathematics formula for single-sum future value.

    Shown in the video
  2. Expression
    FV=10,000(1+0.06)20FV = 10,000(1+0.06)^{20}
    Explanation

    Substitute the known values into the formula.

    Justification

    Direct substitution based on the problem statement.

    Shown in the video
  3. Expression
    FV=10,000(1.06)20FV = 10,000(1.06)^{20}
    Explanation

    Perform the addition inside the parentheses.

    Justification

    Arithmetic simplification.

    Shown in the video
  4. Expression
    FV≈32,071.35FV \approx 32,071.35
    Explanation

    Compute the final numerical result.

    Justification

    Calculator evaluation of the exponential expression.

    Shown in the video
Answer

$32,071.35

Verification

The speaker uses an off-screen calculator to verify the result, stating the final amount aloud and writing it on the board.

Present value of $100,000 ten years from now

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker introduces the second part: “What is the present value of $100,000 ten years from now given the same annual interest rate of 6%?”

  2. Formula
    Observation

    The board writes PV = FV/(1+r1+r)^n=100n = 100,000/(1.06)10=55000/(1.06)^10 = 55,839.48.

Problem

Find the present value of $100,000 received ten years from now at an annual interest rate of 6%.

Given
  1. FV = $100,000

  2. n=10n = 10 years

  3. r=6r = 6% = 0.06

Goal

Compute PV.

Steps
  1. Expression
    PV=FV(1+r)nPV = \frac{FV}{(1+r)^n}
    Explanation

    Use the present-value form of the compound-interest equation.

    Justification

    Rearrange FV = PV(1+r1+r)^n to solve for PV.

    Shown in the video
  2. Expression
    PV=100,000(1+0.06)10PV = \frac{100{,}000}{(1+0.06)^{10}}
    Explanation

    Substitute the given values into the formula.

    Justification

    Direct substitution from the problem statement.

    Shown in the video
  3. Expression
    PV=100,000(1.06)10PV = \frac{100{,}000}{(1.06)^{10}}
    Explanation

    Simplify the denominator base.

    Justification

    Arithmetic simplification: 1+0.06=1.061 + 0.06 = 1.06.

    Shown in the video
  4. Expression
    PV=55,839.48PV = 55{,}839.48
    Explanation

    Evaluate the expression numerically.

    Justification

    Calculator evaluation shown and read aloud in the video.

    Shown in the video
Answer

$55,839.48

Verification

The result is consistent with the displayed formula and the spoken interpretation that this amount today is equivalent in purchasing power to $100,000 ten years later at 6%.

Future value of $10,000 after 20 years at 6%

Clear evidence
Shown in the video
Evidence
  1. Caption evidence
    Observation

    Top prompt reads: 'What is the future value of $10,000 twenty years from now given an annual interest rate of 6%?'

  2. Diagram
    Observation

    Left side shows $10,000 under PV with an arrow labeled 20 yrs and 6% pointing right to $32,071.35 under FV.

Problem

Find the future value of $10,000 twenty years from now at an annual interest rate of 6%.

Given
  1. PV = $10,000

  2. n=20n = 20 years

  3. r=6r = 6% annually

Goal

Compute FV.

Steps
  1. Expression
    PV=10,000,r=0.06,n=20PV = 10{,}000,\quad r = 0.06,\quad n = 20
    Explanation

    Identify the present amount, annual rate, and time horizon from the board.

    Justification

    These values are explicitly written beside the first arrow.

    Shown in the video
  2. Expression
    FV=32,071.35FV = 32{,}071.35
    Explanation

    Read the resulting future value written on the right side of the first example.

    Justification

    The board directly displays $32,071.35 as the FV outcome.

    Shown in the video
Answer

$32,071.35

Verification

The displayed result is consistent with compound growth at 6% for 20 years, though the intermediate calculation is not shown in this clip.

Present value of $100,000 received in 10 years at 6%

Clear evidence
Shown in the video
Evidence
  1. Caption evidence
    Observation

    Top prompt reads: 'What is the present value of $100,000 ten years from now given the same annual interest rate of 6%?'

  2. Diagram
    Observation

    Second row shows $55,839.48 on the left under PV, an arrow labeled 10 yrs and 6%, and $100,000 on the right under FV.

  3. Formula
    Observation

    Bottom-right substitution reads $100,000/(1.06)10000 / (1.06)^10.

Uncertainties
  1. The clip shows the formula setup but not the arithmetic evaluation step from $100,000/(1.06)10000 / (1.06)^10 to $55,839.48.

Problem

Find the present value of $100,000 ten years from now at an annual interest rate of 6%.

Given
  1. FV = $100,000

  2. n=10n = 10 years

  3. r=6r = 6% annually

Goal

Compute PV.

Steps
  1. Expression
    FV=100,000,r=0.06,n=10FV = 100{,}000,\quad r = 0.06,\quad n = 10
    Explanation

    Identify the future amount, annual rate, and time horizon from the second example.

    Justification

    These values are explicitly written on the board and in the top prompt.

    Shown in the video
  2. Expression
    PV=100,000(1.06)10PV = \frac{100{,}000}{(1.06)^{10}}
    Explanation

    Apply the present-value formula with the given numbers.

    Justification

    This exact substitution is written on the bottom-right of the board.

    Shown in the video
  3. Expression
    PV=55,839.48PV = 55{,}839.48
    Explanation

    Read the present-value result shown on the left side of the second example.

    Justification

    The board directly displays $55,839.48 as the PV outcome.

    Shown in the video
Answer

$55,839.48

Verification

The displayed result matches the standard discounting computation for 10 years at 6%, although the clip does not show the intermediate arithmetic.

Comparing $1000 now with $1000 in the future

Clear evidence
Shown in the video
Evidence
  1. Diagram
    Observation

    Third row shows $1000 on the left and $1000 on the right with no interest-rate arrow between them.

  2. Audio
    Observation

    Speaker says: 'The thousand dollars in the present has more purchasing power than the thousand dollars in the future.'

  3. Animation
    Observation

    A red box is drawn around the left $1000 during the spoken comparison.

Uncertainties
  1. The board does not write a numerical discount rate or time length for this $1000 comparison; the interpretation relies on the spoken explanation.

Problem

Interpret the meaning of placing $1000 on both the present-value side and the future-value side.

Given
  1. Left amount: $1000

  2. Right amount: $1000

  3. No explicit rate or period shown between these two $1000 amounts

Goal

Explain why the two equal nominal amounts are not economically equivalent.

Steps
  1. Expression
    1000now≠1000future in economic value1000_{\text{now}} \neq 1000_{\text{future}} \text{ in economic value}
    Explanation

    Although the nominal dollar amounts are equal, the speaker distinguishes the present $1000 from the future $1000.

    Justification

    Audio explicitly states that the present $1000 has more purchasing power than the future $1000.

    Shown in the video
  2. Expression
    Red box around left 1000\text{Red box around left }1000
    Explanation

    The visual emphasis marks the present amount as the more valuable one in the comparison.

    Justification

    Animation shows a red rectangle drawn around the left $1000 while the speaker makes the point.

    Shown in the video
Answer

The present $1000 is treated as more valuable than the future $1000 because money available now has greater purchasing power.

Verification

This example functions as a conceptual illustration rather than a numerical calculation; it aligns with the stated time-value-of-money principle.

Visual events · 6

Cash Flow Timeline Diagram

Clear evidence
Shown in the video
Evidence
  1. Animation
    Observation

    A horizontal timeline is drawn. "$10,000" is written on the left with "PV" above it. An arrow points right, labeled "20 yrs" above and "6%" below. "FV" is written at the tip of the arrow.

Objects
  1. Horizontal arrow representing time

  2. Text labels: PV, $10,000, 20 yrs, 6%, FV

Changes
  1. Drawing of the timeline arrow

  2. Addition of present value and its label

  3. Addition of time and interest rate parameters

  4. Addition of the future value target label

Invariants
  1. The direction of the arrow always points from present to future.

Interpretation

Visually maps the components of the time value of money problem, showing the starting amount, the duration, the growth rate, and the unknown ending amount.

Purchasing-power comparison written on board

Clear evidence
Shown in the video
Evidence
  1. Diagram
    Observation

    The board shows $1→41 \to 4 bags and $1→11 \to 1 bag beneath the earlier future-value work.

  2. Audio
    Observation

    The speaker explains that one dollar buys four bags earlier and one bag later.

Uncertainties
  1. The spoken time reference is internally inconsistent, but the visual contrast itself is clear.

Objects
  1. $1

  2. 4 bags

  3. 1 bag

  4. arrow notation

Changes
  1. The board adds a two-line comparison showing what one dollar buys at different times.

Invariants
  1. The nominal amount remains $1 in both lines.

Interpretation

Holding the dollar amount fixed, the quantity of goods purchasable falls from 4 bags to 1 bag, illustrating loss of purchasing power over time.

Stepwise construction of the present-value calculation

Clear evidence
Shown in the video
Evidence
  1. Diagram
    Observation

    $100,000 is written under FV, then the formula PV = FV/(1+r1+r)^n is written and filled in with 100,000, 1.06, and 10.

  2. Animation
    Observation

    Writing proceeds stepwise from the general formula to the substituted expression and finally the numerical answer.

Objects
  1. PV

  2. FV

  3. (1+r1+r)^n

  4. $100,000

  5. (1.06)^{10}

  6. $55,839.48

Changes
  1. The board first labels the known future amount, then writes the general PV formula, then substitutes values, then simplifies the base, then writes the final dollar result.

Invariants
  1. The interest rate remains 6% throughout the second-part calculation.

  2. The horizon remains 10 years throughout the second-part calculation.

Interpretation

The visual sequence shows the algebraic path from a future amount to its discounted present equivalent.

Interpretive wrap-up after the computation

Clear evidence
Shown in the video
Evidence
  1. Diagram
    Observation

    The completed PV calculation remains visible while the speaker interprets the result.

  2. Audio
    Observation

    The speaker states that $55,839.48 has the same purchasing power as $100,000 ten years later and summarizes the time value of money.

Objects
  1. $55,839.48

  2. $100,000

  3. time value of money statement

Changes
  1. No new formula is introduced; the emphasis shifts from calculation to economic interpretation.

Invariants
  1. The computed numerical result stays on screen as the basis for the conclusion.

Interpretation

The finished arithmetic is used to explain that present and future sums can be equivalent in purchasing power once discounted at the given rate.

Whiteboard organization of PV and FV examples

Clear evidence
Shown in the video
Evidence
  1. Diagram
    Observation

    Static whiteboard layout with PV on the left, FV on the right, arrows showing time and 6% interest, and the formula PV = FV / (1+r1+r)^n at the bottom.

Objects
  1. PV column

  2. FV column

  3. two horizontal arrows labeled with years and 6%

  4. bottom formula PV = FV / (1+r1+r)^n

  5. substitution $100,000/(1.06)10000 / (1.06)^10

Invariants
  1. PV is consistently placed on the left.

  2. FV is consistently placed on the right.

  3. The arrows run from left to right to indicate movement through time.

Interpretation

The layout visually separates present amounts from future amounts and uses arrows to encode the direction of compounding or discounting over time.

Red highlighting of the present $1000

Clear evidence
Shown in the video
Evidence
  1. Animation
    Observation

    A red rectangular outline is drawn around the left $1000 in the third row.

  2. Audio
    Observation

    During this interval the speaker says the present $1000 has more purchasing power than the future $1000.

Objects
  1. left $1000

  2. red rectangle

Changes
  1. A red box appears around the left $1000.

Invariants
  1. The right $1000 remains unboxed.

  2. The rest of the board content stays unchanged.

Interpretation

The animation singles out the present-dollar amount to reinforce the verbal claim that the same nominal sum is more valuable now than later.

Misconceptions · 4

Nominal vs. Real Value

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker explains, "this really helps to illustrate the time value of money. Ten thousand dollars today is worth a lot more than ten thousand in the future... you can buy more of a dollar now than what you could buy twenty years later... now you can buy a small bag of chips for about a dollar. Twenty years ago, you can buy a bag of chips for twenty-five cents."

Misconception

Believing that a fixed nominal amount of money (e.g., $10,000) holds the same purchasing power regardless of when it is received.

Clarification

Due to inflation and the potential to earn interest, money available today has greater purchasing power than the same amount in the future. The example of chip prices illustrates how the real value of a dollar changes over time.

Interest rate and inflation rate are not automatically the same

Clear evidence
Supplementary explanation
Evidence
  1. Audio
    Observation

    The speaker says, “So let’s say that inflation is six percent,” and uses the same 6% rate to interpret purchasing power.

Uncertainties
  1. This is an analyst clarification, not a separate warning stated by the video author.

Misconception

One may think the 6% annual interest rate in the formula is inherently an inflation rate.

Clarification

In the video, 6% is first used as the discount/interest rate in the PV formula; the speaker then adds an interpretive assumption that inflation is also 6% to connect the result to purchasing power. Those roles are conceptually distinct even though the same numerical rate is reused here.

Confusing temporal wording in the purchasing-power example

Approximate timing
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says “twenty years in the past” while describing the chips example, then immediately talks about purchasing power going down as time moves forward.

Uncertainties
  1. The intended direction of the example is clear from context, but the exact spoken temporal wording is inconsistent.

Misconception

The chips example can sound as if it compares the past to the present in a way that contradicts the later statement about future purchasing power.

Clarification

The mathematical point of the example is that the same dollar buys fewer goods later in time; the clip’s wording around “past” is imprecise, but the intended lesson is the decline of purchasing power over time.

Equal nominal amounts are not equal in value across time

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    Speaker says: 'The thousand dollars in the present has more purchasing power than the thousand dollars in the future.'

  2. Animation
    Observation

    The left $1000 is boxed in red while the right $1000 is not.

Misconception

One might think that $1000 today and $1000 in the future are equivalent simply because the numbers are the same.

Clarification

The video explicitly rejects that view by stating that the present $1000 has more purchasing power than the future $1000.

Concept relations · 6

Future Value Formula → Time Value of Money Concepts

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker introduces the formula specifically to "calculate the future value from the present value".

  2. Formula
    Observation

    The formula FV = PV(1+r1+r)^n explicitly defines FV in terms of PV.

Application
Explanation

The future value formula is a mathematical tool used to apply the concept of time value of money, specifically to find the future equivalent of a present sum.

Future value formula already shown on board → Present value formula

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board retains FV = PV(1+r1+r)^n and then writes PV = FV/(1+r1+r)^n.

  2. Audio
    Observation

    The speaker says the formula needs to be rearranged a little before computing present value.

Equivalent
Explanation

The present-value formula is obtained by algebraically rearranging the future-value formula to solve for PV.

Present value formula → Time value of money interpretation

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The computed PV result is used directly in the concluding explanation.

  2. Audio
    Observation

    The speaker says the example “really illustrates the time value of money.”

Application
Explanation

The numerical present-value calculation is the concrete application that demonstrates the broader principle of time value of money.

Purchasing power declines over time → Present value formula

Clear evidence
Shown in the video
Evidence
  1. Diagram
    Observation

    The chips comparison appears before the PV formula is introduced.

  2. Audio
    Observation

    The speaker uses falling purchasing power to motivate why future money is worth less now.

Prerequisite
Explanation

The intuitive purchasing-power example provides the conceptual motivation for discounting future amounts with the PV formula.

Basic idea of the time value of money → Present value formula

Clear evidence
Derived from the video
Evidence
  1. Audio
    Observation

    The speaker states the general time-value-of-money principle.

  2. Formula
    Observation

    The board simultaneously displays PV = FV / (1+r1+r)^n and worked PV/FV examples.

Application
Explanation

The present-value formula is the quantitative tool used to apply the qualitative time-value-of-money principle shown in the examples.

Present value formula → Present value of $100,000 received in 10 years at 6%

Clear evidence
Derived from the video
Evidence
  1. Formula
    Observation

    The bottom formula PV = FV / (1+r1+r)^n is written alongside the numeric examples above.

  2. Diagram
    Observation

    The second example substitutes $100,000 and 10 years into that formula.

Application
Explanation

The $100,000 example is a direct numerical application of the displayed present-value formula.

Find an answer · 12

How do I calculate the future value of a lump sum given the present value, interest rate, and time period?

Clear evidence
Shown in the video
Evidence
  1. Caption evidence
    Observation

    The on-screen text poses the exact question being solved.

Knowledge points
  1. Future Value Formula
  2. Future Value Example Problem

What is the difference between present value and future value?

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker provides definitions for present and future value at the beginning of the video.

Knowledge points
  1. Time Value of Money Concepts

What is the formula for present value used in this clip?

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    PV = FV/(1+r1+r)^n is written explicitly on the board.

Knowledge points
  1. Present value formula

How is the future-value formula rearranged to solve for present value?

Clear evidence
Shown in the video
Evidence
  1. Formula
    Observation

    The board shows both FV = PV(1+r1+r)^n and PV = FV/(1+r1+r)^n.

Knowledge points
  1. Future value formula already shown on board
  2. Present value formula

What is the present value of $100,000 ten years from now at 6% annual interest?

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker states the second-part problem: present value of $100,000 ten years from now at 6%.

  2. Formula
    Observation

    The worked substitution yields $55,839.48.

Knowledge points
  1. Present value formula
  2. Present value of $100,000 ten years from now

Why does the video say money is worth more now than in the future?

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker concludes that the same amount of money is worth more now than in the future.

Knowledge points
  1. Time value of money interpretation
  2. Purchasing power declines over time

How does the clip connect the present-value result to purchasing power under 6% inflation?

Clear evidence
Shown in the video
Evidence
  1. Audio
    Observation

    The speaker says that if inflation is 6%, then $55,839.48 has the same purchasing power as $100,000 ten years later.

Knowledge points
  1. Equivalent purchasing power under 6% inflation
  2. Time value of money interpretation

What is the basic idea of the time value of money?

Clear evidence
Derived from the video
Evidence
  1. Audio
    Observation

    Speaker defines the basic idea behind the time value of money.

Knowledge points
  1. Basic idea of the time value of money

How do you calculate present value from future value?

Clear evidence
Derived from the video
Evidence
  1. Formula
    Observation

    Board shows PV = FV / (1+r1+r)^n.

Knowledge points
  1. Present value formula
  2. Substitution into the present value formula

Why is $1000 today worth more than $1000 in the future?

Clear evidence
Derived from the video
Evidence
  1. Audio
    Observation

    Speaker compares $1000 in the present with $1000 in the future.

  2. Animation
    Observation

    Red box highlights the present $1000.

Knowledge points
  1. Basic idea of the time value of money
  2. Comparing $1000 now with $1000 in the future
  3. Equal nominal amounts are not equal in value across time

What is the present value of $100,000 received 10 years from now at 6%?

Clear evidence
Derived from the video
Evidence
  1. Caption evidence
    Observation

    Top prompt asks for the present value of $100,000 ten years from now at 6%.

  2. Formula
    Observation

    Board shows $100,000/(1.06)10000 / (1.06)^10 and result $55,839.48.

Knowledge points
  1. Present value of $100,000 received in 10 years at 6%
  2. Present value formula

What is the future value of $10,000 after 20 years at 6% annual interest?

Clear evidence
Derived from the video
Evidence
  1. Caption evidence
    Observation

    Top prompt asks for the future value of $10,000 twenty years from now at 6%.

  2. Diagram
    Observation

    Board shows $10,000 growing to $32,071.35.

Knowledge points
  1. Future value of $10,000 after 20 years at 6%
Coverage and review notes

Covered · Introduction to the concepts of present value and future value.

Covered · Presentation of the first example problem and creation of a visual timeline.

Covered · Introduction of the future value formula and step-by-step calculation of the example.

Covered · Conceptual explanation of the time value of money using a real-world purchasing power example.

Covered · Opening board state plus the chips-based purchasing-power explanation and the retained future-value formula.

Covered · Transition to the second part of the problem and setup of the known future value, horizon, and rate.

Covered · Explicit writing of PV = FV/(1+r1+r)^n, substitution of values, and computation of $55,839.48.

Covered · Interpretation of the result as equivalent purchasing power and summary of the time value of money.

Covered · The board is already filled with PV/FV examples and the formula while the speaker explains that $1000 now has more purchasing power than $1000 in the future; the left $1000 is highlighted with a red box.

Covered · The speaker states the general time-value-of-money principle while the static whiteboard continues to show the PV/FV examples and the formula PV = FV / (1+r1+r)^n.

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