Posted by Jake on Thursday, December 9, 2010 at 8:39pm.
An alloy of metals is 25% copper .Another alloy is 50% copper. How much of each alloy should be used to make 1000grams of an alloy that is 45% copper?

8th grade  TutorCat, Thursday, December 9, 2010 at 11:11pm
.25(x)+.50(1000x)=.45(1000)
where x is the number of grams of 25% copper
and 1000x is the rest of the 1000 grams i.e. the number of grams of 50%