What is the sample space in this meeting problem?
Conditions
- Time is normalized such that 4:00 PM is 0 and 5:00 PM is 1.
- and represent the arrival times of the two people.
- Arrivals are independent and uniform on (modeling assumption).
Reasoning, step by step
- Normalize the time interval 4:00–5:00 to .
- Define variables and for the two arrival times.
- Construct the set of ordered pairs .
- Identify the region as .
Example
The script states: 'Let be the two arrival times in these units. Each lies in , so the possible pairs fill a unit square.'
Common misconceptions
- Thinking the sample space is a line segment.
- Assuming the sample space includes times outside 4:00–5:00.
- Confusing the sample space with the event region (meeting band).
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