The tread life a certain brand of tires is known to be norma

The tread life a certain brand of tires is known to be normally distributed with a mean of 60,000 miles and a standard deviation of 3,100 miles.
Answer
a) What is the probability that a randomly selected tire will last longer than 55,200 miles.
Answer
b) Determine P (58,000 < Tire Life < 61,500)
c) The company wishes to set the warranty so that only 2.5% of the tires will need to be replaced. What should the warranty mileage be.

Solution