I am a two-digit number whose square is also a two-digit number. What number am I?
Category: Math · Difficulty: expert
Hint: Think about the range of squares for two-digit numbers.
Answer
76
Explanation
76 is the only two-digit number whose square, 5776, is a four-digit number and its digits sum to 20.
This is a expert math riddle — one of the harder riddles here. The answer is 76.
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