I am a number with four digits. All of my digits are different. My thousands digit is three times my units digit, and my hundreds digit is the sum of my thousands and units digits. My tens digit is zero. What number am I?
6802
Let the number be abcd. We know c = 0. We are told a = 3d, and b = a + d. Since a must be a single digit between 1 and 9, d can be 1, 2, or 3. If d = 2, then a = 6 and b = 6 + 2 = 8. Thus, the digits are 6, 8, 0, and 2.
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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