This is an OVERLAPPING SETS question. The easiest way to solve is by using a DOUBLE SET MATRIX:



We can fill in what we know from the question stem: If 20 percent of all employees have one year or more of experience and no advanced degree, what percentage of employees have advanced degrees and less than one year of experience?



Now, fill in the information from statement 1:
(1) 35 percent of the employees do not have advanced degrees and 55 percent have less than one year of work experience.



Because we know that each row & column sums to the total, we can make further inferences:



We have a value for the percentage of employees have advanced degrees and less than one year of experience. Sufficient.

Important process note: for DS overlapping sets, make sure you erase what you learned from statement (1) before approaching statement (2). You may even want to make 2 separate matrices.

(2) 15 percent of the employees lack an advanced degree and have less than one year of work experience; 45 percent have one year or more of experience.



Now infer:


We have a value for the percentage of employees have advanced degrees and less than one year of experience. Sufficient.

The answer is D.

Overlapping Sets are a common question type on the GMAT, and the double-set matrix is often the easiest way to solve.

For more on how to use the matrix, see:
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