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3. The standard deviation (6) of 20-29 year olds body weight is 40lbs. How many adults will be needed to have 95% confidence?
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Answer #1

Given:

\small \sigma = 40

E = 10

For 95% confidence, z = 1.96

Hence,

Sample size required

\small n = (1.96*40/10)^2

n = 62

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