In mixing a weed killing chemical a 40% solution of the chemical is mixed with an 85% solution to get 20 L of a 60% solution. How much of each solution is needed?

Answer 1

If x at 40%, the rest (20-x) is 85%. So,

.40x + .85(20-x) = .60(20)

Answer 2

amount of 40% stuff --- x L
amount of 85% stuff --- 20-x L

.4x + .85(20-x) = .60x

Answer 3

go with Steve, I messed up, right side is .60(20)