SOLUTION: A population is estimated to have a standard deviation of 11. We want to estimate the population mean within 3, with a 90% level of confidence. (Use z Distribution Table.)
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-> SOLUTION: A population is estimated to have a standard deviation of 11. We want to estimate the population mean within 3, with a 90% level of confidence. (Use z Distribution Table.)
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Question 1091933: A population is estimated to have a standard deviation of 11. We want to estimate the population mean within 3, with a 90% level of confidence. (Use z Distribution Table.)
How large a sample is required? (Round the z-values to 2 decimal places. Round up your answer to the next whole number.)
You can put this solution on YOUR website! We use the following formula to solve this problem
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E = z(a/2) * (s/square root(n)), where
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E is the required difference between the sample mean and the population mean
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z(a/2) is the positive z value for a(alpha)/2
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s is the standard deviation of the population
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n is the number for the sample size
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n = ( z(a/2) * s / E )^2
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a = 1 - (90/100) = 0.10
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z(0.05) = 1.65
:
n = ( 1.65 * 11 / 3)^2 = 36.6025
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the sample required is 37
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