3. The mean time required to repair breakdowns of a certain copying machine is 93 minutes.

The company which manufactures the machines claims that breakdowns of its newer model

are easier to fix. To test this claim, a sample of 18 breakdowns of the new model were

observed, resulting in a mean repair time of 86.8 minutes with a standard deviation of 14.6

minutes. Using a significance level of a = 0.10, determine if the new copy machines are faster

to repair. State clearly what your null and alternative hypotheses are, show your work, and

state your conclusion.