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Confidence Intervals

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A recent study indicated that 29% of the 100 women over age 55 in the study were widows.

a. How large a sample must one take to be 90% confident that the estimate is within 0.05 of the true proportion of women over ages 55 who are widows?

b. If no estimate of the sample proportion is available how large should the sample be?

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Solution Summary

This solution explains how confidence intervals are affected by different sample sizes.

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