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## Official Guide Explanation:Data Sufficiency #92

Background

This is just one of hundreds of free explanations I've created to the quantitative questions in The Official Guide for GMAT Review (12th ed.). Click the links on the question number, difficulty level, and categories to find explanations for other problems.

These are the same explanations that are featured in my "Guides to the Official Guide" PDF booklets. However, because of the limitations of HTML and cross-browser compatibility, some mathematical concepts, such as fractions and roots, do not display as clearly online.

Question: 92
Page: 280
Difficulty: 6 (Moderately Difficult)
Category 1: Word Problems > Sets >
Category 2: Arithmetic > Sets > 3+ sets
Category 3: Arithmetic > Percents > other

Explanation: If 60 percent of the employees are over 40 and 30 percent of those have master's degrees, we can find the number of employees who are over 40 and have master's degrees if we know the total number of employees.

Statement (1) is sufficient: we know that 50% of the employees are college graduates, so if 100 of the employees are college graduates, then there are 200 total employees. Given that number, we can find the number of over - 40 employees, and from there, the number of those employees with master's degrees.

Statement (2) is insufficient: we need a number of employees, and this is just a percent. The correct choice is (A).

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