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H. E. Dudeney, Amusements in Mathematics (1917) No. 59 · Puzzles · Age & time puzzles

A Puzzling Watch

A friend pulled out his watch and said, "This watch of mine does not keep perfect time; I must have it seen to. I have noticed that the minute hand and the hour hand are exactly together every sixty-five minutes." Does that watch gain or lose, and how much per hour?

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H. E. Dudeney, Amusements in Mathematics (1917) · No. 59

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