“龟鹤同池，龟鹤共100只，共有脚350只，问龟鹤各多少只？”设龟有x只，鹤有y只，则下列方程组中正确的是_刷题宝

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“龟鹤同池，龟鹤共100只，共有脚350只，问龟鹤各多少只？”设龟有x只，鹤有y只，则下列方程组中正确的是（　　）

A： $\{\begin{matrix} x + y = 100 \\ 2 x + 4 y = 350 \end{matrix}$

B： $\{\begin{matrix} x + y = 100 \\ 4 x + 2 y = 350 \end{matrix}$

C： $\{\begin{matrix} x - y = 100 \\ 4 x + 2 y = 350 \end{matrix}$

D： $\{\begin{matrix} x - y = 100 \\ 2 x + 4 y = 350 \end{matrix}$

上一题下一题 0.0难度选择题更新时间:2014-07-05 05:32:22

答案(点此获取答案解析）

B

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