2002 AMC 10B Problems/Problem 14
Problem
The number is the square of a positive integer . In decimal representation, the sum of the digits of is
Solution
Taking the root, we get .
Now, we have .
Combining the 's and 's gives us .
This is the number with a string of sixty-four 's at the end. Thus, the sum of the digits of is
See also
2002 AMC 10B (Problems • Answer Key • Resources) | ||
Preceded by Problem 13 |
Followed by Problem 15 | |
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All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.
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