I am a two-digit prime number less than 30. Dividing me by 4 leaves a remainder of 3. Adding 2 to me turns me into a multiple of 5. What number am I?
23
Primes under 30 are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29. Two-digit primes that leave a remainder of 3 when divided by 4 are 11, 19, and 23. Adding 2 to 23 gives 25, which is a multiple of 5.
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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