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信息发布者:
B
5x
5y
5y = 5x + 100
2x
2y
2x + 2y = 100
$\begin{cases}\dfrac{x}{4}+\dfrac{y}{5}=\dfrac{54}{60}\\\dfrac{x}{6}+\dfrac{y}{5}=\dfrac{42}{60}\end{cases}$
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