I am a two-digit integer greater than 50. When you square me, the final two digits of the resulting product are identical to my original value. What number am I?
76
76 squared equals 5,776, which ends in the digits 76. It is an automorphic number greater than 50.
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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