SOLUTION: The 12 monthly averages of daily high temperatures for San Antonio are given in the data set that follows. The high temperature on April 1 was 45° F. What was the z-score for that

Algebra ->  Statistics  -> Describing-distributions-with-numbers -> SOLUTION: The 12 monthly averages of daily high temperatures for San Antonio are given in the data set that follows. The high temperature on April 1 was 45° F. What was the z-score for that       Log On


   

Question 1089133: The 12 monthly averages of daily high temperatures for San Antonio are given in the data set that follows. The high temperature on April 1 was 45° F. What was the z-score for that day?
48.5, 52.5, 63.2, 68.9, 73.9, 81.4, 85.6, 85.1, 78.8, 70.7, 59.6, 51.0
a. –1.75
b. –1.86
c. 1.75
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

The sample size is n = 12

The sample mean is approximately m = 68.2667 (add up the values and divide by n = 12)

The sample standard deviation is approximately s = 13.2923 (use a calculator)

If the raw score is x = 45, then the z-score is...

z+=+%28x-m%29%2F%28s%29

z+=+%2845-68.2667%29%2F%2813.2923%29

z+=+%28-23.2667%29%2F%2813.2923%29

z+=+-1.7504

z+=+-1.75

This value is approximate

Therefore the final answer is choice A