1994 AJHSME Problems/Problem 25
Contents
[hide]Problem
Find the sum of the digits in the answer to
where a string of nines is multiplied by a string of fours.
Solution 1
Notice that:
and
and
So the sum of the digits of 9s times 4s is simply (Try to find the proof that it works for all values of ~MATHWIZARD10).
Therefore the answer is
Solution 2
See Also
1994 AJHSME (Problems • Answer Key • Resources) | ||
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