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2002 AMC 12A Problems/Problem 6

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The following problem is from both the 2002 AMC 12A #6 and 2002 AMC 10A #4, so both problems redirect to this page.

Contents

Problem

For how many positive integers m does there exist at least one positive integer n such that m \cdot n \le m + n?

\mathrm{(A) \ } 4\qquad \mathrm{(B) \ } 6\qquad \mathrm{(C) \ } 9\qquad \mathrm{(D) \ } 12\qquad \mathrm{(E) \ } infinitely many


Solution 1

For any m we can pick n=1, we get m \cdot 1 \le m + 1, therefore the answer is \boxed{\text{(E) infinitely many}}.


Solution 2

Another solution, slightly similar to this first one would be using Simon's Favorite Factoring Trick.

(m-1)(n-1) \leq 1

Let n=1, then

0 \leq 1

This means that there are infinately many numbers m that can satisfy the inequality. So the answer is \boxed{\text{(E) infinitely many}}.

See Also

2002 AMC 12A (ProblemsResources)
Preceded by
Problem 5
Followed by
Problem 7
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
2002 AMC 10A (ProblemsResources)
Preceded by
Problem 3
Followed by
Problem 5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
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