# 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.”