Question

A pharmacist has 18% bleach solution. How much of this solution and how much water must be mixed together to make 10 liters of a 12% solution?

Answer 1

X = the amount of water to add
10 - x = amount of 18% bleach to add

.18(10-x)= .12 x 10
1.8 -.18x =1.2
-.18x = -.6
x = 3 1/3 liters water
therefore 6 2/3 liters bleach