# Question: a company manufactures batteries which have an expected life following...

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A company manufactures batteries which have an expected life following a normal distribution with a mean of 50,000 hours and a standard deviation of 7,500 hours.

(a) Sketch the normal distribution and shade the area that corresponds to the probability that a battery will last less than 40,000 hours.

(b) Calculate the z value of the standard normal that corresponds to a battery life of 65,000 hours.

(c) What is the median life for these batteries?