I am a two-digit number. My tens digit is twice my units digit, and the sum of my digits is 9. What number am I?
63
Let the units digit be x. The tens digit is 2x. Their sum is x + 2x = 3x = 9, so x = 3. Therefore, the tens digit is 6 and the units digit is 3, making the number 63.
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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