A company surveyed a group of 25 employees about their daily commute times. The table below shows the frequency distribution of the commute times, where one frequency is represented by the variable .
| Commute Time (minutes) | Number of Employees |
|---|---|
| 10 | 5 |
| 20 | 8 |
| 30 | |
| 45 | 4 |
| 60 | 3 |
If the mean commute time for all 25 employees is 28.8 minutes, what is the median commute time, in minutes, for these 25 employees?
- A5
- 20Answer
- C25
- D28.8
- E30
Answer
The median commute time for the 25 employees is 20 minutes.
To find the median commute time, we first determine the missing frequency . Since the total number of employees is 25, we set up the equation , giving . With 25 total values ordered from smallest to largest, the median is the 13th value. Counting through the frequencies in order, the first 5 employees have a commute time of 10 minutes, and the next 8 employees (positions 6 through 13) have a commute time of 20 minutes. Therefore, the 13th employee's commute time is 20 minutes.
Step-by-Step Solution
Key Concept
Calculating the median from a frequency distribution table with a total count constraint.