Last Updated on May 5, 2023
GMAT OFFICIAL GUIDE DS
Solution:
An easy way to solve this problem is to set up a double set matrix. In our matrix, we have two main categories: biology and chemistry. More specifically, our table will be labeled with:
1) Number of people who are enrolled in chemistry (Chem)
2) Number of people who are not enrolled in chemistry (No Chem)
3) Number of people who are enrolled in biology (Bio)
4) Number of people who are not enrolled in biology (No Bio)
(To save room on our table headings we will use the abbreviations for the categories.)
We need to determine the difference between the number of students who are enrolled in both chemistry and biology and the number of students who are enrolled in neither course.
Statement One Alone:
In College X there are 60 students enrolled in a chemistry course.
Let’s fill the information from statement one into our table.
The information in statement one is not enough to answer the question. We can eliminate answer choices A and D.
Statement Two Alone:
In College X there are 85 students enrolled in a biology course.
The information in statement two is not enough to answer the question. We can eliminate answer choice B.
Statements One and Two Together:
Without more information, we cannot answer the question.
Answer: E
