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问答题
A farmer has a field containing a certain number of pigs and hens. Between them they have 36 heads and 100 feet. How many pigs and hens does the farmer have?
参考答案
参考解析
解析：
假设有x头猪，y只鸡，那么可得以下方程组：
x+y=36
4x+2y=100
解此方程组可得x=14,y=22。
假设有x头猪，y只鸡，那么可得以下方程组：
x+y=36
4x+2y=100
解此方程组可得x=14,y=22。
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