2011 AMC 10B Problem 1

Problem 1 of 25EasierAlgebra

What is the value of the following expression?

\dfrac{2+4+6}{1+3+5} - \dfrac{1+3+5}{2+4+6}

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Solution

Simply solving directly:

\begin{aligned} &\dfrac{2+4+6}{1+3+5} - \dfrac{1+3+5}{2+4+6} \\ &= \dfrac{12}9 - \dfrac 9{12} \\ &= \dfrac {16}{12} - \dfrac 9{12} \\ &=\dfrac 7{12}. \end{aligned}

Thus, the correct answer is C .

Concepts: fraction · order of operations

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