Question

How much of an alloy that is 10% copper should be mixed with 600 ounces of an alloy that is 60% copper in order to get an alloy that is 20% copper?

Answer 1

Answer:

1800 oz.

Step-by-step explanation:

There are already 600 ounces of alloy of nickel.

Of this 600 oz, 50% is pure i.e. copper content = 600(0.5) = 300 oz

Now available is

Copper      Other metals

300                 300

Let x oz of 10% copper is added.

Then new alloy will have 300+0.1x oz copper in total of 600+x oz.

Percentage pure = $\frac{300+0.1x}{600+x} =20%$

Simplify to get

$\frac{300+0.1x}{600+x} =\frac{20}{100} \\\\Cross multiply:\\20(600+x) =100(300+0.1x)\\12000+20x =30000+10x\\10x = 18000\\x = 1800$

Hence answer is 1800 oz should be added.