Question

HELP ASAP PLEASEE!! a metal alloy weighing 4 mg and containing 20% iron is melted and mixed with 12 mg of a different alloy which contains 40% iron. which percent of the resulting alloy is iron?

A)12%

B)20%

C)35%

D)55%

Answer 1

35 percent

Explanation:

To solve this problem we multiply the amount by the percent and add them up to get the total amount times the percent

amount * percent + amount * percent = total amount * percent

4 * .20 + 12 * .40 = (4+12) * x

.8 + 4.8 = 16 x

Combine like terms

5.6 = 16x

Divide by 16

5.6/16 = 16x/16

.35 =x

35 percent