Question

A vehicle parts company makes shocks. They currently guarantee their shocks for 50,000 miles. The distance traveled before the shocks fail is normally distributed with mean 63,000 and standard deviation 10,000.

1. What % of shocks will be replaced at no charge to the customer?
2. What % of shocks will fail at exactly 50,000 miles?
3. What % of shocks will fail between 40,000 and 55,000 miles?
4. At what number of miles is there a 90% that the shock will have previously failed?

Answer 1