# A golf pro believes that the variances of his driving distances are different for different brands of golf balls

A golf pro believes that the variances of his driving distances are different for different brands of golf balls. In particular, he believes that his driving distances, measured in yards, have a smaller variance when he uses Titleist golf balls than when he uses a generic store brand. He hits 10 Titleist golf balls and records a sample variance of 150.43. He hits 13 generic golf balls and records a sample variance of 339.72. Assume that both population distributions are approximately normal and test the golf pro’s claim using a 0.05
level of significance. Does the evidence support the golf pro’s claim? Let the pro’s driving distances using Titleist golf balls be Population 1 and let the pro’s driving distances using generic store brand golf balls be Population 2.
State the null and alternative hypotheses for the test. Fill in the blank below.

H0Ha: σ21=σ22: σ21 ?= σ22
c. Draw a conclusion and interpret the decision.