QUESTION 1

1. Compute the range for the set of data.

0.133, 0.117, 0.54, 0.383, 0.573, 0.276

1. Find the population mean or sample mean as indicated.

Sample: 7, 9, 15, 17, 22

1. Find the sample standard deviation.

128, 185, 281, 280, 103, 109, 245, 256, 223

A severe drought affected several western states for 3 years. A Christmas tree farmer is worried about the drought's effect on the size of his trees. To decide whether the growth of the trees has been retarded, the farmer decides to take a sample of the heights of 25 trees and obtains the following results (recorded in inches):

The tree farmer feels the normal height of a tree that was unaffected by the drought would be 65 inches. Find the z-score for a tree that is 65 inches tall.