A grandfather clock takes 5 seconds to strike 6 o'clock. Assuming the strikes are evenly spaced, how many seconds will it take to strike 12 o'clock?
11 seconds
Striking 6 times leaves 5 intervals between strikes, so each interval lasts 5 / 5 = 1 second. Striking 12 times creates 11 intervals, taking 11 seconds in total.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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