I am a prime number between 10 and 20. If you reverse my digits, you get another prime number, and if you add my digits together, you get 8. What number am I?
17
The prime numbers between 10 and 20 are 11, 13, 17, and 19. Adding the digits of 17 gives 1 + 7 = 8. Reversing 17 gives 71, which is also a prime 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: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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