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3 years ago

How many oz. of a metal containing 40%

Mathematics

1 answer:

RideAnS [48]3 years ago

3 0

Answer:

3 oz

Step-by-step explanation:

Let x represent the number of oz. of the medal with 40% gold:

Set up an equation and solve for x:

0.4x + 7(0.9) = 0.75(x + 7)

0.4x + 6.3 = 0.75x + 5.25

6.3 = 0.35x + 5.25

1.05 = 0.35x

3 = x

So, you will need 3 oz. of the metal with 40% gold

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