DATA SUFFICIENCY
This section consists of problems in which a question on any topic such as Coding-Decoding, Puzzle Test, Blood Relations, Mathematical calculations etc., is put forward, followed by certain statements containing facts providing clues to solve the question. The candidate is required to find out which of the given statements is/are sufficient to answer the given question. These questions are about working out what is necessary and sufficient data to be able to answer a question.
Example: Four subjects — Physics, Chemistry, Mathematics and Biology were taught in four consecutive periods of one hour each starting from 8.00 a.m. At what time was the Chemistry period scheduled?
(I) Mathematics period ended at 10.00 a.m. which was preceded by Biology.
(II) Physics was scheduled in the last period.
(III) Mathematics period was immediately followed by Chemistry.
(a) Only I
(b) Only I or Only II
(c) Only II
(d) II and III together
(e) I and II together or I and III together
Answer: From I and II, we conclude that Mathematics period began at 9.00 a.m., Biology period began at 8.00 a.m. and Physics period at 11 a.m. So, the Chemistry period began at 10.00 a.m.
From I and III, we conclude that Mathematics period ended and Chemistry period began at 10.00 a.m. So the correct answer is (e).
Example: How many sons does X have?
(I) Q and U are brothers of T.
(II) R is sister of P and U.
(III) R and T are daughters of X.
(a) I and II only
(b) II and III together
(c) I, II and III together
(d) I, II and III together are not sufficient
(e) None of these
Answer: (e) The information given in the three statements together is also not sufficient to answer the given question.