Question 201532
How many milligrams of pure water must be added to 6 mg of a 40% solution to obtain a 25% solution?
.
Let x = milligrams of water added
then
.40(6) = .25(6+x)
2.4 = 1.5 + .25x
0.9 = .25x
3.6 mg = x (amount of pure water)