Prelims 2026 · CSAT / Logical Reasoning · Question 36
There are four statements X, Y, Z and W. Their relations are as follows:<br/>If X is incorrect, then so is Z; if Y is incorrect, then W is correct; if W is correct, then X is incorrect.<br/>Which of the following is/are correct?<br/>I. If X is correct, then so is Y.<br/>II. If Z is correct, then it is not necessary that Y is correct.<br/>Select the answer using the code given below.<br/>
Answer
I only
Given: ¬X → ¬Z, ¬Y → W, and W → ¬X. From ¬Y → W → ¬X, we get ¬Y → ¬X, so by contrapositive X → Y. Hence I is correct. Also, ¬X → ¬Z gives the contrapositive Z → X; and since X → Y, we get Z → Y. So if Z is correct, Y must be correct. Hence II is false.