I am a prime number. If you flip me upside down, I become a different prime number that is 12 greater than the original. What number am I?
59
Flipped upside down, 59 looks like 65? No, 59 flipped is 66? Wait. 5 flipped is 2 or something? Let's use 19 and 61: 19 flipped is not standard. Let's use 3 and 8? Let's use a valid math puzzle: I am an odd number, take away a letter and I become even. What number am I? (Answer: Seven). Wait, prompt requires math riddles. Let's do: My digits add up to 8. I am a multiple of 11. I am greater than 50. What number am I?
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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