A quarter of the time since noon plus half the time till tomorrow noon is right now
A professor announces: if you add one quarter of the time elapsed since noon today to half of the time remaining until noon tomorrow, you get the exact current time. Nobody has a clock handy. What time is it?
Reveal the answer
9:36 p.m. A quarter of the 9 hours 36 minutes since noon is 2 hours 24 minutes; half of the 14 hours 24 minutes left until noon tomorrow is 7 hours 12 minutes. Added together, those two give exactly 9 hours 36 minutes — the time itself. Henry Dudeney set this as puzzle No. 57 in Amusements in Mathematics (1917).
— Henry Ernest Dudeney, Amusements in Mathematics — 1917, Puzzle No. 57, 'What Was the Time?'
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