If the population standard deviation of the lifetime of washing machines is estimated to be 900...

If the population standard deviation of the lifetime of washing machines is estimated to be 900 hours, how large a sample must be taken in order to be 96% confident that the margin of error will not exceed 100 hours?

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Expert Solution

The minimum sample is calculated as

N=344

Z is calculated using Z table shown below , normal curve

orchestra answered 1 year ago

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