A study of the effects of smoking on sleep patterns is conducted. The measure observed is the time, in minutes, that it takes to fall asleep. These data are obtained:

- Smokers: 69.3, 56.0, 22.1, 47.6, 53.2, 48.1, 52.7, 34.4, 60.2, 43.8, 23.2, 13.8
- Nonsmokers: 28.6, 25.1, 26.4, 34.9, 29.8, 28.4, 38.5, 30.2, 30.6, 31.8, 41.6, 21.1, 36.0, 37.9, 13.9

(a) Find the sample mean for each group.

To find the sample mean for each group (smokers and nonsmokers), you need to calculate the average of the given data for each group separately.

For smokers:

Data for smokers: 69.3, 56.0, 22.1, 47.6, 53.2, 48.1, 52.7, 34.4, 60.2, 43.8, 23.2, 13.8

To find the sample mean for smokers, add up all the values and divide by the number of data points (12 in this case):

Sample mean for smokers = (69.3 + 56.0 + 22.1 + 47.6 + 53.2 + 48.1 + 52.7 + 34.4 + 60.2 + 43.8 + 23.2 + 13.8) / 12

Sample mean for smokers ≈ 42.58 minutes

Now, for nonsmokers:

Data for nonsmokers: 28.6, 25.1, 26.4, 34.9, 29.8, 28.4, 38.5, 30.2, 30.6, 31.8, 41.6, 21.1, 36.0, 37.9, 13.9

To find the sample mean for nonsmokers, add up all the values and divide by the number of data points (15 in this case):

Sample mean for nonsmokers = (28.6 + 25.1 + 26.4 + 34.9 + 29.8 + 28.4 + 38.5 + 30.2 + 30.6 + 31.8 + 41.6 + 21.1 + 36.0 + 37.9 + 13.9) / 15

Sample mean for nonsmokers ≈ 31.273 minutes

So, the sample mean for smokers is approximately 42.58 minutes, and the sample mean for nonsmokers is approximately 31.273 minutes.

To know more about sample mean, refer here:

https://brainly.com/question/33323852

#SPJ4