# GMAT Data Sufficiency: Answer Choices and Method | topin GMAT guidesData Sufficiency Section Data Insights (moved from Quant in the Focus Edition) Format A question, two statements, five fixed answer choices Content Maths or logic and verbal reasoning Calculator On-screen calculator available in Data Insights Time per question About 2 minutes; usually one of the faster Data Insights types ## How it works The five answer choices are always the same. A: statement (1) alone is sufficient, but statement (2) alone is not. B: statement (2) alone is sufficient, but statement (1) alone is not. C: both statements together are sufficient, but neither alone is. D: each statement alone is sufficient. E: the statements together are not sufficient. A statement is sufficient if it gives exactly one value, or one definite yes or no. ## Worked example Is the positive integer n divisible by 6? (1) n is divisible by 3\. (2) n^2 is divisible by 12. 1. AStatement (1) ALONE is sufficient, but statement (2) alone is not sufficient. 2. BStatement (2) ALONE is sufficient, but statement (1) alone is not sufficient. 3. CBOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient. 4. DEACH statement ALONE is sufficient. 5. EStatements (1) and (2) TOGETHER are NOT sufficient. Show the answer B Statement (1): n = 3 gives no, n = 6 gives yes. Not sufficient. Statement (2): 12 = 4 x 3, so n^2 is divisible by 3 and by 4\. Because 3 is prime, 3 dividing n^2 means 3 divides n. And n must be even, since an odd n gives an odd n^2\. So n is divisible by 2 and 3, and therefore by 6, for every n that fits. Checks: 6, 12 and 18 all fit and are all divisible by 6\. Sufficient, so the answer is B. The trap is C: people assume (2) only shows n is even and reach for (1) to supply the 3. ## A method for Data Sufficiency 1. 1 ### Know the choices by heart Remember the order as 1 alone, 2 alone, together, each, neither. You should never spend test time reading the choices. 2. 2 ### Pin down the question Is it asking for a single value or a yes or no? Simplify it first: 'is n divisible by 6?' becomes 'is n divisible by both 2 and 3?'. 3. 3 ### Test statement (1) alone Try to find two cases that fit it and give different answers. If you can, it is insufficient. If every case gives the same answer, it is sufficient. After this, only A and D, or only B, C and E, remain. 4. 4 ### Test statement (2) alone, forgetting (1) Clear statement (1) from your mind completely. Carrying its information across is the most common Data Sufficiency error. 5. 5 ### Combine only if both fail Put the statements together and test again. If two cases still fit both and give different answers, choose E. 6. 6 ### Stop once sufficiency is clear You need to know that an answer exists, not what it is. Solving to the end wastes time you need for Multi-Source Reasoning and tables. ## Traps to avoid * Treating a definite 'no' as insufficient. A statement that always gives 'no' is sufficient. * Using statement (1) while judging statement (2) alone. * Assuming a variable is a positive integer when the question does not say so; test negatives, zero and fractions. * Choosing C when one statement is secretly sufficient on its own, as in the worked example. * Counting equations instead of checking them: two equations can be the same line and give no unique answer. ## Data Sufficiency FAQs What are the five GMAT Data Sufficiency answer choices? A: (1) alone is sufficient, (2) alone is not. B: (2) alone is sufficient, (1) alone is not. C: both together are sufficient, neither alone is. D: each alone is sufficient. E: together they are not sufficient. Is Data Sufficiency still on the GMAT Focus Edition? Yes. It moved from Quant to Data Insights, and it can now test logic and verbal reasoning as well as maths. Can I use the calculator on Data Sufficiency? Yes, the on-screen calculator is available for all of Data Insights. You rarely need it, since you are judging sufficiency rather than computing an answer. Is 'no' a sufficient answer in Data Sufficiency? Yes. If a statement always leads to 'no', you can answer the question, so it is sufficient. Only a mix of yes and no is insufficient. ## Try Data Sufficiency under real timing Your first full-length GMAT mock is free, with every section included. [Take the free mock ](/gmat/login)