A pharmacist mixes 14 ounces of 68% saline solution with 55% saline solution. If the final mixture is 62% saline, how many ounces of the 55% solution were used?

2 answers

let amount of 55% solution be x ounces
then amount of 68% solution is 14-x

solve for x:

.55x + .68(14-x) = .62(14)
multiply by 100
55x+ 68(14-x) = 62(14)

take over....
55x+68(14-x)=62(14)
55x+143-68x=868
55x-68x=725