Question 198175
let x="grams of 10% Au alloy", and y="grams of 30% Au alloy"


(10%)x + (30%)y = 60 ___ multiplying by 3 ___ (30%)x + (90%)y = 180


(15%)x + (40%)y = 88 ___ multiplying by 2 ___ (30%)x + (80%)y = 176


subtracting ___ (10%)y = 4 ___ dividing by 10% ___ y = 40


substituting ___ (10%)x + (30%)(40) = 60 ___ (10%)x + 12 = 60 ___ (10%)x = 48


dividing by 10% ___ x = 480