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题目
A grocery customer spent a total of $9.6 for ground beef and coffee.The coffee cost 2 times as much per pound as the ground beef,and the customer bought 3 times as many pounds of ground beef.How much,in dollars,did the customer spend on coffee

提问时间:2020-07-18

答案
设卖牛肉次数为y,价格为a,买咖啡次数为z,价格为c,据题意,得
2a=c (1)
y=3z (2)
ay+cz=9.6 (3)
他球的是咖啡总价,即cz=,
所以要用有cz的式子表示,变形(1)得a=c/2,
吧(1)(2)代入得1.5cz+cz=9.6
2.5cz=9.6
cz=3.84
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