The life expectancy of Timely brand watches is normally distributed with a mean of four years and a standard deviation of eight months.
a.What is the probability that a randomly selected watch will be in working condition for more than five years?
b.The company has a three-year warranty period on their watches. What percentage of their watches will be in operating condition after the warranty period?
c.What are the minimum and the maximum life expectancy of the middle 95% of the watches?
d.Ninety-five percent of the watches will have a life expectancy of at least how many months?

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The Answer of The life expectancy of Timely brand watches is normally distributed with a mean of four years and a standard deviation of eight months.
a.What is the probability that a randomly selected watch will be in working condition for more than five years?
b.The company has a three-year warranty period on their watches. What percentage of their watches will be in operating condition after the warranty period?
c.What are the minimum and the maximum life expectancy of the middle 95% of the watches?
d.Ninety-five percent of the watches will have a life expectancy of at least how many months?

The Life Expectancy of Timely Brand Watches Is Normally Distributed