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As the new manager of a small convenience store, you want to understand the shop

ID: 3127388 • Letter: A

Question

As the new manager of a small convenience store, you want to understand the shopping patterns of your customers. You randomly sample 20 purchases from yesterday's records. The amounts of those purchases (in dollars) are shown to the right. Complete parts a) through c). Standardize the minimum and maximum purchase using a mean of46.24 and a standard deviation of 21.95. The z-score for the minimum purchase is -1.908 and the z-score for the maximum purchase is 2.072. Which has the more extreme z-score, the min or the max? The max z-score is more extreme. How large a purchase would a purchase with a z-score of 3.5 be? A purchase with a z-score of 3.5 would be S.

Explanation / Answer

c)

As

x = u + z*sigma

Then

x = 46.24 + 3.5*21.95 = 123.065 [ANSWER]