SOLUTION: 9. The life span of a battery is normally distributed, with a mean of 2500 hours and a standard deviation of 50 hours. What percent of batteries have a life span that is more than

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Question 872378: 9. The life span of a battery is normally distributed, with a mean of 2500 hours and a standard deviation of 50 hours. What percent of batteries have a life span that is more than 2575 hours? Would it be unusual for a battery to have a life span that is more than 2575 hours? Explain yours reasoning.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Population: mean of 2500 hours and a standard deviation of 50 hours

P(x >2575)

z = 75/50 = 3/2 = 1.5

P(z > 1.5) = normalcdf(1.5,10) =  .0668 0r 6.68%