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QUESTION 7. The life expectancy of a particular brand of tire is normally distributed with a...

QUESTION 7. The life expectancy of a particular brand of tire is normally distributed with a mean of 40,000 and a standard deviation of 5,000 miles. (8 points)

2 Points each

a. What is the probability that a randomly selected tire will have a life of no more than 50,000 miles?

b. What is the probability that a randomly selected tire will have a life of at least 47,500 miles?

c. What percentage of tires will have a life of 34,000 to 46,000 miles?

d. What is the probability that a randomly selected tire will have a life of exactly 47,500 miles?

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