Solution

(related to Problem: The Hydroplane Question)

The machine must have gone at the rate of seven-twenty-fourths of a mile per minute and the wind traveled five-twenty-fourths of a mile per minute. Thus, going, the wind would help, and the machine would do twelve-twenty-fourths, or half a mile a minute, and returning only two-twenty-fourths, or one-twelfth of a mile per minute, the wind being against it. The machine without any wind could, therefore, do the ten miles in thirty-four and two-sevenths minutes, since it could do seven miles in twenty-four minutes.


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References

Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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