Chapter 3, Problem 1CQQ

Sleep Mean As part of the National Health and Nutrition Examination Survey, subjects were asked how long they slept the preceding night, and the following times (hours) were reported: 8, 7, 5, 7, 4, 7, 6, 7, 8, 8, 8, 6. Find the mean.

To determine

To find: The mean hours slept by the subjects in the preceding night.

Answer to Problem 1CQQ

The mean hours slept by the subjects in the preceding night is 6.8 hours.

Explanation of Solution

Given info:The data shows thenumber of hours slept by the subjects. The number of hours of sleep by the subjects is 8, 7, 5, 7, 4, 7, 6, 7, 8, 8, 8, and 6

Calculation:

The formula for mean is,

$\overline{x}=\frac{{\displaystyle \sum x}}{n}$

Mean hours slept by the subjects in the night is,

$\begin{array}{c}\overline{x}=\frac{8+7+5+7+4+7+6+7+8+8+8+6}{12}\\ =\frac{81}{12}\\ =6.8\end{array}$

Thus, the mean hours slept by the subjects in the preceding night is 6.8 hours.