# Confidence Interval

Assume a mean 0f 110 and a standard deviation of 10 in a population,

a. What proportion of the population has levels greater than 115 and less than 105?

b. If repeated sample of 30 were selected, what proportion of them would have less than 100?

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Answer (a):

Use the following formula in ...

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The solution provides excellent answer to the problem below about confidence intervals.

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