Medium
Each digit of a 5 digit number is 1. It is multiplied by itself. What is the sum of the digits of the resulting number?
Explanation
Explanation
Step 1: The 5-digit number in which every digit is 1 is 11111. Step 2: Multiply it by itself: 11111 × 11111 = 123454321. Step 3: Add the digits of the result: 1 + 2 + 3 + 4 + 5 + 4 + 3 + 2 + 1 = 25. So the sum of the digits of the resulting number is 25.
PRO TIP
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