I have four legs when I am born, two legs when I grow up, and three legs when I am old. Wait, that's a Sphinx riddle! Let's do math: I am a two-digit number. If you add my digits, you get 9. If you swap my digits, the new number is 45 less than me. What am I?
72
7 + 2 = 9. 72 - 27 = 45. The digits swapped give 27, which is 45 less than 72.
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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