1973 AHSME Problems/Problem 31
Problem
In the following equation, each of the letters represents uniquely a different digit in base ten:
The sum equals
Solution
The right side of the equation can be rewritten as . With trial and error and prime factorization as a guide, we can test different digits of to see if we can find two two-digit numbers that have the same units digit and multiply to .
The only possibility that works is . That means .
See Also
1973 AHSME (Problems • Answer Key • Resources) | ||
Preceded by Problem 30 |
Followed by Problem 32 | |
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