Question 1121904
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A sculptor wants to cast a bronze statue from an alloy that is 60% copper. He has 30 kilos of a 40% alloy. How much 80% copper alloy should he mix it with to obtain the 60% copper alloy?
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x, number of kilograms of the 80% copper


{{{(80x+40*30)/(x+30)=60}}}