A wall clock strikes once at 1 o'clock, twice at 2 o'clock, and so on. How many total times does it strike during a single 12-hour period?
78 times
Sum the numbers from 1 to 12: 1 + 2 + 3 + ... + 12 = (12 * 13) / 2 = 78.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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