<PRE><B>Question 273154</B>
Researchers want to estimate the mean weight of all chipmunks living in Albuquerque, NM. Using the population standard deviation of 1.4 ounces as in Question #5, find the sample size required if we want our margin of error to be less than 0.25 ounces with 95% confidence. 
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Since E = z*s/sqrt(n)
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sqrt(n) = zs/E
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n = [zs/E]^2
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Your Problem:
n = [1.96*1.4/0.25]2
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n = 120.47
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Rounding up:
n = 121
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Cheers,
Stan H.</PRE>