Each data sufficiency problem is composed of a question and two statements, labeled (1) and (2), which contain certain data. Using this data and your knowledge of mathematics and everyday facts (such as "the number of how many in one day", etc..), you are asked to decide whether the data given is sufficient for answering the question. Although it has a unique format it does not focus on specific mathematical topics covered in the quantitative section, and can contain any topic, just as the problem solving question format does.
Question format
The data sufficiency question format is:
(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked.
(C) BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
(D) EACH statement ALONE is sufficient to answer the question asked.
(E) Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.
Take a data sufficiency practice test
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