<PRE><B>Question 618465</B>
how much of an alloy that is 40% copper should be mixed with 100 ounces of an alloy that is 70% copper in order to get an alloy that is 50% copper?
:
Let x amt of 40% alloy
:
.40x + .70(100) = .50(x+100)
:
.40x + 70 = .50x + 50
70 - 50 = .50x - .40x
20 = .10x
x = 20/.1
x = 200 oz of 40% alloy
:
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