### How to Solve GMAT Data Sufficiency Questions

Data Sufficiency questions are the most popular in the GMAT. They do not require a particular answer from the candidates but to determine whether the given information is enough to solve the question. Of the quantitative section, 1/3rd of the questions are of this type.
Some ways to solve the data sufficiency problems are described below:

1. If there are equations in your statement, do not forget to check how many variables are present in the question. There will be that many answers. So, you can eliminate choices that have a single answer for a two variable equation and so on.
2. When coming across questions that have exponents, try to find ways to reduce the expression by canceling out possible variables. When the question becomes easier, there are chances that you will get it right.
3. When there is a geometry problem at hand, carefully study the diagram and understand it. Try to locate what is asked in the question in the diagram so you can find your answer.
4. Do not assume anything about the question. Only read the facts that are given and answer.
5. If you cannot figure out more than one statement, worry not. You can eliminate two choices right away and make a guess between the other three. There will be a 33% chance that your answer will be correct.
Sample Question: Is m divisible by 6?
1. m is divisible by 3
2. m is divisible by 4
Let's glance at the basic concepts of all data sufficiency questions. In the Quantitative section of the GMAT, they represent about half the number of questions. The question is of the form, a mathematical problem followed by two statements with data. Candidates have to choose one of following five possible solutions. The answers will always be:
A. Statement 1 ALONE is sufficient but statement 2 alone is not sufficient.
B. Statement 2 ALONE is sufficient but statement 1 alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement alone is sufficient.
D. EACH statement ALONE is sufficient.
E. Statements 1 and 2 TOGETHER are NOT sufficient.
EXPLANATION:
We need to determine whether m is divisible by 6. The answer has to be a definitive YES or a NO.

To check if a number is divisible by 6, one should check if it is divisible by both 3 and 2.

From statement (1) we can conclude that m can by divided by 3.

However, we do not know for certain that m is divisible by 2 also.

Hence, statement (1) alone is not sufficient.

We can eliminate the answer choices (A) and (D). The correct answer has to be (B), (C) or (E).

From statement (2) we can conclude that m is divisibly by 4. If m is divisible by 4, then m should definitely be divisible by 2.

However, from statement (2) alone we do not know if m is divisible by 3.

Therefore, statement (2) alone is also not sufficient. Hence, we can eliminate answer choice (B).

Combining the two statements, we know that m is divisible by 3 and by 4.

Hence, we can conclude that m is divisible by 6.