The Phillies were accused of cheating their beer customers by not putting enough beer in their 12 oz cups. When 15 cups were selected at random, they were found to have a mean of 11.7 ounces with a standard deviation of 0.5 ounces. At the .01 significance level, test the claim that the customers are being cheated.

Answer 1

Z = (score-mean)/SEm = (11.7-12)/SEm

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability (.01) related to the Z score.