
Question: In a certain office, 50 percent of the employees are college graduates and 60 percent of the employees are over 40 years old. If 30 percent of those over 40 have master's degrees, how many of the employees over 40 have master's degrees?
(1) Exactly 100 of the employees are college graduates.
(2) Of the employees 40 years old or less, 25 percent have master's degrees.
“In a certain office, 50 percent of the employees are college” is a topic of the GMAT Quantitative reasoning section of GMAT. The GMAT Data Sufficiency questions consist of a problem statement and two factual statements. This specific GMAT data sufficiency question estimates the candidates’ skill in analyzing the problem and solving it with their mathematical knowledge. The most challenging part of these questions arises from smart wording that is overlooked by the candidates. The GMAT Quant section contains 31 MCQs to be completed within 62 minutes. The GMAT data sufficiency comprises 15 questions which are two-fifths of the 31 GMAT quant questions.
Solution and Explanation:
Approach Solution 1:
The problem statement informs that:
Given:
Find Out:
Let the total number of employees in the office be x
Therefore, as per the question, college graduates = 0.5x
Employees over 40 years old = 0.6x
Employees over 40 having master’s degrees= 0.3*0.6x
Therefore, we can conclude that
0.5x = 100
Therefore, x= 200
Thus from this statement, we can discover the value of x and hence we can determine the value of 0.3*0.6x.
Thus, the number of employees over 40 having master’s degrees = 0.3* 0.6* 200 = 36
Therefore the statement alone is sufficient to get the value of the number of employees over 40 having master's degrees.
Thus, the statement alone is not sufficient to find the value of employees over 40 having master’s degrees.
Correct Answer: A
Approach Solution 2:
The problem statement declares that:
Given:
Find Out:

According to the question, 30% of the employees over 40 years old have master's degrees. It is given that 60 percent of the employees are over 40 years old.
Therefore, we can say that 30% of 60% of total employees have master's degrees = 18% of the total employees have master’s degrees.
Therefore, the problem statement asks to find the value of this 18% of the total employees.
It is given that 50% of the total employees are college graduates. Therefore, 50% of the total is equal to 100.
This gives the total number of employees present in the company.
Therefore, it would help us to give the value of 18% of total employees.
Thus statement (1) alone is sufficient to find the number of employees over 40 having master's degrees.
Therefore, the statement gives only the percentage information. It is required to provide one actual value to obtain the number of employees who are 40+ years old and have master’s degrees. Without any actual number, it is not possible to find the value of employees over 40 having master's degrees.
Thus statement (2) alone is insufficient to find the value of employees.
Correct Answer: A
Approach Solution 3:
The problem statement claims that:
Given:
Find Out:

We need to find the value of E and therefore, we are dealing with one variable. One equation is required to correspond to the number of variables and equation.
50E = 100
Therefore, E=2
As per the question, 30% of 60% of employees over 40 have master's degrees = 18E over 40 have master’s degrees.
Therefore, 18E= 18*2 = 36
Thus the statement alone is sufficient.
40E*25% = 10E = x
But it is not possible for us to find the value of E. Therefore, the condition in this statement alone is not sufficient.
Correct Answer: A
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