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来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/08/13 00:29:54
(1)甲两次购买粮食共需付粮款(100x+100y)元,乙两次共购买 (
100 x + 100 y ) kg粮食. q 1 = 100x+100y 2×100 = x+y 2 , q 2 =100×2÷( 100 x + 100 y )=200÷ 100x+100y xy = 2xy x+y . (2)q 1 -q 2 = x+y 2 - 2xy x+y = (x-y) 2 2(x+y) >0 ,故乙的购粮方式合算. |