Mental Floss
PUZZLE

This 'Marriage' Logic Puzzle Stumps Over 70 Percent of People Who Attempt It—See How You Fare

Jake Rossen
See if you can vow to solve this tricky logic puzzle.
See if you can vow to solve this tricky logic puzzle. / EkaterinaPichukova/iStock via Getty Images (Married Couple) // ahmad agung wijayanto/Shutterstock (Question Marks)
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Puzzles, riddles, and brainteasers abound online, and we’ve passed along several, including this entrance exam math problem from MIT circa 1876 and a baffling family tree riddle that’s confounded most who try it.

Another entry in the most-people-won’t-solve-it genre: A recent puzzler courtesy of MindYourDecisons.com that the site claims stumps 80 percent of players. (A similar question posed by The Guardian in 2016 resulted in a 72 percent miss rate among 200,000 respondents.)

Here’s the question:

Alice is looking at Bob, and Bob is looking at Charlie. Alice is married, Charlie is not.

Is a married person looking at an unmarried person?

A. Yes

B. No

C. Cannot Be Determined

The answer appears below.

the word 'answer' in a blue text bubble
Justin Dodd/Mental Floss

The answer is A. A married person is looking at an unmarried person because our friend Bob’s marital status works either way. If Bob is married, and we know he’s looking at the unmarried Charlie, the statement holds true. If Bob is unmarried, and the married Alice is looking at him, the statement still stands.

Here’s another one courtesy of the same site:

You have a drawer with 10 black socks and 10 white socks. You close your eyes and pull out three socks. Are you holding a matching pair of socks?

A. Yes

B. No

C. Cannot Be Determined

the word 'answer' in a blue text bubble
Justin Dodd/Mental Floss

The answer is A. (Yes) because only two possibilities exist. If you take two socks from the drawer, either the pair will be matched or you’ll have one black and one white sock. Taking a third sock will be black or white, meaning it will pair up with one of the first two.

If you’re now intrigued by sock mysteries, check out the reason why washing machines appear to eat your footwear.

[h/t Mind Your Decisions]

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