I am an odd three-digit number. All three of my digits are different. My tens digit is the sum of my hundreds and units digits. The sum of all my digits is 12. What number am I?
264
Digits must sum to 12. Tens digit equals hundreds plus units, meaning tens must be half of the total sum (12 / 2 = 6). Hundreds and units must sum to 6. Testing odd numbers where hundreds plus units equals 6 and digits are unique yields 264 (2+4=6, and 2+6+4=12).
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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