1997 AHSME Problems/Problem 1
Problem
If and are digits for which
then
Solution
From the units digit calculation, we see that the units digit of is . Since and is an integer, the only value of that works is is . As a double-check, that does work, since , which is the first line of the multiplication.
The second line of the multiplication can be found by doing the multiplication . Dividing both sides by gives .
Thus, , and the answer is .
See Also
1997 AHSME (Problems • Answer Key • Resources) | ||
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