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Estimation, Confidence Interval for proportions

A random sample of 90 prisoners in a large state prison revealed that 20% were college graduates. Find the 99% confidence interval in the population sampled for the percentage of prisoners who are college graduates.

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p=proportion of college graduates= 20.00%
q=1-p= 80.00%
n=sample size= 90
s p=standard error of proportion= square root of (pq/n)= 4.22% = square root of ( 20.% * ...

Solution Summary

The solution calculates the 99% confidence interval in the population sampled for the percentage of prisoners who are college graduates.

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