2.125 Exercise and adequate sleep. A survey of 656 boys and girls, who were 13 to 18 years old, asked about adequate sleep and other health-related behaviors. The recommended amount of sleep is six to eight hours per night.²⁸ In the survey, 59% of the respondents reported that they got less than this amount of sleep on school nights. An exercise scale was developed and used to classify the students as above or below the median in this domain. Here is the 2 × 2 table of counts with students classified as getting or not getting adequate sleep and by the exercise variable:

1. (a) Find the distribution of adequate sleep for the high exercisers.

2. (b) Do the same for the low exercisers.

3. (c) Summarize the relationship between adequate sleep and exercise using the results of parts (a) and (b).