SOLUTION: A chemist has a 15% silver alloy and a 30% silver alloy. How much of each alloy is need to be mixed to obtain 25 kg of an alloy that is 20% silver? (show work)
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-> SOLUTION: A chemist has a 15% silver alloy and a 30% silver alloy. How much of each alloy is need to be mixed to obtain 25 kg of an alloy that is 20% silver? (show work)
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Question 630992: A chemist has a 15% silver alloy and a 30% silver alloy. How much of each alloy is need to be mixed to obtain 25 kg of an alloy that is 20% silver? (show work) Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! A chemist has a 15% silver alloy and a 30% silver alloy. How much of each alloy is need to be mixed to obtain 25 kg of an alloy that is 20% silver? (show work)
.
Let x = amount (kg) of 15% silver
then
25-x = amount (kg) of 30% silver
.
.15x + .30(25-x) = .20(25)
.15x + 7.5-.30x = 5
7.5-.15x = 5
-.15x = -2.5
x = -2.5/(-.15)
x = 2.5/(.15)
x = 250/15
x = 50/3
x = 16.67 kg (15% silver)
.
30% silver:
25-x = 25-16.67 = 8.33 kg
