2012 AMC 10B Problems/Problem 10: Difference between revisions
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<math> \textbf{(A)}\ 6\qquad\textbf{(B)}\ 7\qquad\textbf{(C)}\ 8\qquad\textbf{(D)}\ 9\qquad\textbf{(E)}\ 10 </math> | <math> \textbf{(A)}\ 6\qquad\textbf{(B)}\ 7\qquad\textbf{(C)}\ 8\qquad\textbf{(D)}\ 9\qquad\textbf{(E)}\ 10 </math> | ||
== Solution 1 == | == Solution 1 == | ||
Revision as of 19:43, 3 September 2021
Problem 10
How many ordered pairs of positive integers
satisfy the equation
Solution 1
Cross-multiplying gives
We write
as a product of two positive integers:
The products
and
each produce
ordered pairs
as we can switch the order of the factors. The product
produces
ordered pair
Together, we have
ordered pairs
~Rguan (Solution)
~MRENTHUSIASM (Reformatting)
See Also
| 2012 AMC 10B (Problems • Answer Key • Resources) | ||
| Preceded by Problem 9 |
Followed by Problem 11 | |
| 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 | ||
| All AMC 10 Problems and Solutions | ||
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