How many were at the meeting before anyone walked out?
A dispute at a meeting caused some members to walk out. The chairwoman said afterward, "If I had left too, two-thirds of us would have gone." Another member replied, "But if you'd also managed to keep me and one other person from leaving, we'd only have lost half our number." How many people were at the meeting to start with?
Reveal the answer
Eighteen people were present, and eleven left. One more leaving (twelve) would be exactly two-thirds of eighteen; two fewer leaving (nine) would be exactly half. Henry Dudeney posed this as 'The Suffragists' Meeting,' puzzle no. 107 in Amusements in Mathematics (1917).
— Henry Ernest Dudeney, Amusements in Mathematics — 1917, puzzle no. 107
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