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

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Courses

Fallacy Detectors

Fallacy Detectors

Develop the skills to tackle logical fallacies through a series of 10 science-fiction videos with activities. Recommended for ages 8 and up.

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A Statistical Odyssey

A Statistical Odyssey

Learn about common mistakes in data analysis with an interactive space adventure. Recommended for ages 12 and up.

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Logic for Teens

Logic for Teens

Learn how to make sense of complicated arguments with 14 video lessons and activities. Recommended for ages 13 and up.

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Emotional Intelligence

Emotional Intelligence

Learn to recognize, understand, and manage your emotions. Designed by child psychologist Ronald Crouch, Ph.D. Recommended for ages 5 and up.

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Worksheets

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Logical Fallacies Worksheets and Lesson Plans

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Worksheets covering the basics of symbolic logic for children ages 12 and up.

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Elementary School Worksheets and Lesson Plans

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Middle School Worksheets and Lesson Plans

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High School Worksheets and Lesson Plans

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Statistical Shenanigans Worksheets and Lesson Plans

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