# It is desired to estimate the time it takes Statistics I students

It is desired to estimate the time it takes Statistics I students to finish a computer project to within 2 hours at 95% reliability. It is estimated that the standard deviation of the times is 14 hours. How large a sample should be taken to get the desired interval? Hint: Think about margin of error.

**Solution: **The 95% margin of error is equal to

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We need to be within 2 hours, which means that

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which means that the sample size should be at least 189.

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