shanon needs 20g of 80% of gold to make a pendan. she has some 85% gold and some 70% gold, from broken jewelry and wants to know how much she should use. determine the quantity of each alloy that she should use.

Answer 1

amount of 85% gold ---> x g
amount of 70% gold ---> 20-x

solve for x :
.85x + .7(20-x) = .8(20)

Answer 2

thanks :)