There are three loops in a tangle of rope. How many are independent, and how many are interlocked?
Two knights stand on a chessboard. How many other knights must you add so that each square is occupied or threatened by a knight?
Among six seemingly identical drawings of mandalas, each rotated by multiples of 60 degrees, one is different. Which is it, and why?
Challenge yourself with these mind-benders, brainteasers, and puzzles. Each of them has been carefully selected so that none will be too tough for anyone without a math background but they're not too easy. Some are original, and all are clearly and accurately answered at the back of the book.
by Pierre Berloquin, Martin Gardner
by Henry David Thoreau
by Charles Darwin
by Mark Twain
by Charles Dickens
by Frederick Douglass
by Alexis de Tocqueville
by Elizabeth Gaskell
by Carlo Collodi
by Joshua Slocum
by James Fenimore Cooper
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