Question 343876
 A stationery store wants to estimate the mean retail value of greeting cards that it has in its inventory. A random sample of 20 greeting cards indicates an average value of $1.67 and a standard deviation of $0.32. 
a. Assuming a normal distribution, set up a 95% confidence interval estimate of the mean value of all greeting cards in the store,s inventory.
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x-bar = 1.67
E = (1.96)(0.32/sqrt(20)) = 0.1402
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95% CI: 1.67-0.1402 < u < 1.67+0.1402
95% CI: 1.5298 < u < 1.8102
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b. How might the results obtained in (a) be useful in assisting the store owner to estimate the total value of her inventory?
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Assuming there are "x" cards in the store the inventory value
is between $1.53x and $1.81x.
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Cheers,
Stan H.
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