I am a multi-digit number composed entirely of 1s. If my value is multiplied by 3, the sum of all the digits in the new product equals 3. How many digits do I have?
1 digit
The only single-digit number composed of 1s is 1. 1 * 3 = 3, and the sum of its digits is 3. (If it were 11, 11*3=33, sum is 6).
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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