2001 AMC 12 Problems/Problem 2
Revision as of 14:02, 16 February 2008 by Brut3Forc3 (talk | contribs) (New page: == Problem == Let <math>P(n)</math> and <math>S(n)</math> denote the product and the sum, respectively, of the digits of the integer <math>n</math>. For example, <math>P(23) = 6</math> and...)
Problem
Let and denote the product and the sum, respectively, of the digits of the integer . For example, and . Suppose is a two-digit number such that . What is the units digit of ?
Solution
Denote and as the tens and units digit of , respectively. Then . It follows that , which implies that . Since , . So the answer is .
See Also
2001 AMC 12 (Problems • Answer Key • Resources) | |
Preceded by Problem 1 |
Followed by Problem 3 |
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All AMC 12 Problems and Solutions |