What number multiplied by itself gives a product that ends with the same two digits as the number itself?
Category: Math · Difficulty: medium
Hint: Look for numbers called automorphic numbers.
Answer
A number twenty five
Explanation
Twenty-five squared is six hundred twenty-five, which ends with twenty-five, meeting the criteria.
This is a medium math riddle — a moderate challenge for most people. The answer is A number twenty five.
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