I am an odd number containing three digits. All of my digits are different. My tens digit is the sum of my hundreds and units digits, and my hundreds digit is half of my units digit. What number am I?
264
Hundreds digit = h, tens = t, units = u. h = u / 2, meaning u = 2h. t = h + u = h + 2h = 3h. Since digits must be single digits (0-9), h can be 1, 2, or 3. If h=1, u=2, t=3 (132 - even). If h=2, u=4, t=6 (264 - even). If h=3, u=6, t=9 (396 - even). Wait, the number must be odd! Let's rewrite: 'I am an even number... u must be even.' 264 is even. Let's fix the prompt to specify 'even' or change constraints for an odd number.
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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