SOLUTION: Please help, I keep trying to work this problem and I keep getting the wrong answer when I go back to check! An alloy of gold and silver weighs 150 ounces, 30 ounces of which ar

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Question 719853: Please help, I keep trying to work this problem and I keep getting the wrong answer when I go back to check!
An alloy of gold and silver weighs 150 ounces, 30 ounces of which are gold. If the alloy is to be recast, how much silver must be added to produce an alloy that is 5% gold?
Thanks!
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
An alloy of gold and silver weighs 150 ounces, 30 ounces of which are gold. If the alloy is to be recast, how much silver must be added to produce an alloy that is 5% gold?
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Equation:
Percent gold in the alloy: 30/150 = 0.20
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gold + gold = gold
0.20*150 + 0*x = 0.05(150+x)
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20*150 + 0 = 5*150 + 5x
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5x = 15*150
x = 3*150 = 450 oz (amt. of silver to add)
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Cheers,
Stan H.

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Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
At the start ounces are gold and
ounces are silver
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You are not changing the ounces of gold
only the ounces of silver
Let = ounces of silver to be added

450 ounces of silver must be added
check:

OK