An antique wall clock chimes once at half past every hour, and on the hour it strikes the exact number of times matching the hour (e.g., three strikes at 3:00). Starting at 1:00 AM and ending right after the strikes of 1:00 PM, how many total strikes and chimes will the clock produce?
91
From 1:00 AM to 12:00 PM, the hourly strikes sum to 1 + 2 + ... + 12 = 78. At 1:00 PM, it strikes 1 more time (79 total). There are 12 half-past chimes (1:30 AM through 12:30 PM). 79 + 12 = 91.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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