Four Cards Puzzle

We must flip card E. E is a vowel. If card E does not have an even number on the other side, the statement is not true.

We must flip card 5. If card 5 has a vowel on the other side, the statement is not true.

We must flip card N. If card N has a vowel on the other side, the statement is not true. Nothing says that each hard has one letter and one number!

We don’t need to flip card 8. Whatever card 8 has on the other side (vowel, consonant, or number), the statement is not disproven. Remember: “If a card has a vowel on one side, then it has an even number on the other side” does not mean the same thing as “If a card has an even number on one side, then it has a vowel on the other side.”

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More Puzzles

You can buy a printable version of these puzzles.

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