Question 571776
You are given the sample mean and standard deviation to construct 90% and 95% confidence interval 
random sample 49 gas grills has a mean of $633.20 and a standard deviation of $59.20
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90% CI:
x-bar = 633.20
ME = 1.645[59.2/sqrt(49)] = 13.91
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90% CI: 633.20-13.91 < u < 633.20+13.91
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For the 95% CI use z = 1.96
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cheers,
Stan H.