A team of psychologists studying narcolepsy (a sleep disorder characterized by sudden nodding off during the day) decided to follow 20 narcoleptic volunteers throughout the course of one day and record how many times they each fell asleep. The data they collected have been arranged in the following simple frequency distribution:
| Number of Times Asleep |
f (frequency) |
| 7 |
2 |
| 6 |
1 |
| 5 |
3 |
| 4 |
5 |
| 3 |
3 |
| 2 |
4 |
| 1 |
2 |
N = 20
Find (a) the mode, (b) the median, and (c) the mean.