Multiple choice general knowledge math & puzzles

Which is logically equivalent to "If today is Sunday, Matt cannot play hockey."?

  1. Today is Sunday and Matt can play hockey.

  2. If Matt plays hockey, then today is not Sunday.

  3. Today is Sunday and Matt cannot play hockey.

  4. Today is not Sunday if and only if Matt plays hockey.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The contrapositive of 'If P then Q' is 'If not Q then not P,' and these are logically equivalent. Here P is 'today is Sunday' and Q is 'Matt cannot play hockey.' The contrapositive becomes 'If Matt CAN play hockey (not Q), then today is NOT Sunday (not P)' - option B. Option C merely restates the original. Options A and D are not equivalent.

AI explanation

The original conditional is 'Sunday → not hockey.' Its contrapositive, 'hockey → not Sunday' (i.e., if Matt plays hockey, today is not Sunday), preserves the same truth value in all cases. A conjunction of the two clauses or a biconditional is a stronger or different claim and isn't logically equivalent to the original if-then statement.