Question

The distribution of results from a cholesterol test has a mean of 180 and a standard deviation of 20. A sample size of 40 is drawn randomly.

Find the sum that is one standard deviation below the mean of the sums. (Round your answer to two decimal places.)

Answer 1

= 180

= 20

A sample of size n = 40 is taken from this population.

The distribution of the sample sum has the mean and standard deviation ad

= n* = 40 * 180 = 720

=   = 20*40 = 126.49

The value of sum which is one standard deviation below the mean is   - (1*)

- (1*) = 720 - (1* 126.49) = 593.51