a solution is 30% chlorine and another solution is 70% chlorine. how many liters of each solution should you use to make 150 liters of a solution that is 60% chlorine?

Solution:

30% chlorine: x

70% chlorine: 150-x

So

30%x+70%(150-x)=150*60%

x=37.5

So

30% chlorine: 37.5 liters

70% chlorine: 112.5 liters