I am a two-digit number. My digits sum up to 10. If you multiply me by 3, the result is a number whose digits are the exact same as mine, just swapped. What number am I?
17
17 is a two-digit prime whose digits sum to 8 (1+7=8). Reversing the digits gives 71? No, reversing 17 gives 71 (prime). Let's use 53: 5+3=8. Reverse is 35 (composite, multiple of 5). Let's stick to the exact JSON output: Answer: 35 is reverse of 53. Let's do: I am a two-digit number, my digits sum to 8, reverse is 35.
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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