<PRE><B>Question 1028409</B>
A jeweler has 30 oz of an alloy consisting of 60 percent gold and 40 percent silver. How much of a second alloy containing 80 percent gold and 20 percent silver must be mixed with the first alloy to obtain an alloy containing 75 percent gold and 25 percent silver? 
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Equation:
gold + gold = gold
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0.6*30 + 0.8x = 0.75*(30+x)
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60*30 + 80x = 75*30 + 75x
5x = 15*30
x = 90 oz (amt. of 80% needed)
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Cheers,
Stan H.
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