Official Guide Explanation:
Data Sufficiency #32

Background

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Solution and Metadata

Question: 32
Page: 275
Difficulty: 4 (Moderately Easy)
Category 1: Word Problems > Other >
Category 2: Arithmetic > Descriptive Statistics > Average

Explanation: We don't need to worry specifically about the 7 percent sales tax. The more important question is the total cost of the items subject to the tax--that is, the total cost of the items that cost more than $100 each.

Statement (1) is insufficient. Since the coat cost $125, that leaves $240 for the other six items. It's possible that the other six items were all less than $100 each; for instance, each of the items could be $40 each. However, one of the items could be $140 and the other five could be $20 each.

Statement (2) is also insufficient. If the average of the other six items is $40, those items total $240, meaning that the coat cost $125. That's the same information that (1) gave us, so the result must be the same, as well.

Taken together, the statements are still insufficient. They tell us the same thing, so combining them does not give us any information we didn't have looking at either statement indepedently. Choice (E) is correct.

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