A book has its pages numbered consecutively from 1 through 100. How many times does the printed numeral digit '7' appear across all pages?
20 times
The digit 7 appears 10 times in the units position (7, 17, 27... 97) and 10 times in the tens position (70 through 79), totaling 20 occurrences.
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: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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