# Question: An educator wants to determine the difference between the proportion

An educator wants to determine the difference between the proportion of males and females who have completed 4 or more years of college. What sample size should be obtained if she wishes the estimate to be within 2 percentage points with 90% conﬁdence, assuming that

(a) she uses the 1999 estimates of 27.5% male and 23.1% female from the U.S. Census Bureau?

(b) she does not use any prior estimates?

(a) she uses the 1999 estimates of 27.5% male and 23.1% female from the U.S. Census Bureau?

(b) she does not use any prior estimates?

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