A chemist has one solution containing 30% insecticide and another solution containing 50% insecticide. How much of each solution should the chemist mix to get 200 L of a 42% insecticide?
He or she should use
Amount of substance = concentration x volume.
Because the total amount of insecticide does not change
we can set up 2 simultaneous equations:
Substitute this for
Substitute this back into