Often we are interested not just in a single mean but in a difference in means between two groups. In the Student Survey data, there are 36 seniors: 26 males and 10 females. Table 2.17 gives the number of hours per week that each said he or she spent exercising.

Table 2.17

(a) Calculate xÌ…_f, the mean number of hours spent exercising by the females.
(b) Calculate xÌ…_m, the mean number of hours spent exercising by the males.
(c) Compute the difference, xÌ…_m ˆ’ xÌ…_f, and interpret it in context.

Transcribed Image Text:

Females 4 2 5 12 15 10 5 5 Males 10 10 5 4 12 12 15 10 5 5 3 5 15 6. 6. 5 5 6470