Official Guide Explanation:
Data Sufficiency #77




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Solution and Metadata

Question: 77
Page: 279
Difficulty: 5 (Moderate)
Category 1: Word Problems > Other >
Category 2: Arithmetic > Percents > other

Explanation: This is a concept that the GMAT repeatedly tests. The salesman's compensation can be representated as follows, where s is his sales:

300 + 0.05(s - 1000)

Statement (1) is sufficient. We know that his compensation is equal to 10% of his sales, so we can set that equal to the other way we can express his compensation:

0.1s = 300 + 0.05(s - 1000)

0.1s = 300 + 0.05s - 50

0.05s = 250

s = 5000

Once we know his sales, we can calculate his compensation.

Statement (2) is also sufficient. Given his sales and the expression derived from the question, we can calculate his compensation:

300 + 0.05(s - 1000)

300 + 0.05(5000 - 1000)

300 + 0.05(4000)

300 + 200 = 500

Choice (D) is correct.

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