A book has 120 pages. How many times does the digit '7' appear in total when numbering all the pages from 1 to 120?
22
Count the 7s in the units place (7, 17, 27... 117 = 12 times) and the tens place (70 through 79 = 10 times). 12 + 10 = 22.
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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