I am a two-digit prime number. Reverse my digits, and I remain a prime number. Add my digits together, and you get 10. My tens digit is larger than my ones digit. What am I?
73
Two-digit numbers with tens > ones whose digits sum to 10 are 91, 82, 73, and 64. 73 is prime, and its reverse, 37, is also prime.
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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