Question 351274
In a chemistry class, 3 liters of a 4% silver iodine solution must be mixed with a 10% solution to get a 6% solution. How many liters of the 10% solution are needed?

Let x = amount of 10% solution
then
3-x = amount of 4% solution

.10x + .04(3-x) = .06(3)
.10x + .12-.04x = .18
.06x + .12 = .18
.06x = .06
x = 1 liter (amount of 10% solution)