38 views

P, Q, R, S are four statements. Relation between these statements is as follows:

If P is true then Q must be true.

If Q is true then R must be true.

If S is true then either Q is false or R is false.

Then which of the following must be true?

1. If P is true then S is false
2. If S is false then Q must be true
3. If Q is true then P must be true
4. If R is true then Q must be true