Question

Suppose that the lifetimes of TV tubes are normally distributed with a standard deviation of 1.1 years. Suppose also that exactly 40% of the tubes die before 5 years. Find the mean lifetime of TV tubes. Carry your intermediate computations to at least four decimal places. Round your answer to at least one decimal place.

Answer #1

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Problem Page Suppose that IQ scores in one region are normally
distributed with a standard deviation of 15 . Suppose also that
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four decimal places. Round your answer to at least one decimal
place.

Lifetimes of AAA batteries are approximately normally
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