How many ounces of pure nickel must be added to 150 ounces of alloy 70% pure to make an alloy which is 85% pure?

150 oz.

Step-by-step explanation:

There are already 150 ounces of alloy of nickel.

Of this 150 oz, 70% is pure i.e. nickel content = 150(0.7) = 105 oz

Now available is

Nickel       Other metals

105                  45

Let x oz of pure nickel is added.

Then new alloy will have 105+x oz nickel in total of 150+x oz.

Percentage pure =

Simplify to get

Hence answer is 150 oz should be added.

y + 11 = (1/4)(x + 16)

step-by-step explanation: