A brake pad manufacturer claims its brake pads will last for 38,000 miles. You work for a consumer protection agency and you are testing this manufacturer's brake pads. Assume that the life span of brake pads are normally distributed. You randomly select 49 brake pads. In your tests, the mean life pad of the brake pads is 37,650 miles. Assume standard deviation of the population of brake pads is 1000 miles.
A. Assuming that the manufacturer's claim is correct, what is the probability the mean of the sample is 37,650 miles or less?
B. Using your answer from part (A), what do you think of the manufacturer's claim?
C. Would it be unusual to have an individual brake pad last for 37,650 miles? Why or Why not?