Question

A pharmacist wishes to mix a solution that is 6% Minocidil. She has on hand 60 ml of a 3% solution and wishes to add some 8% solution to obtain the desired 6% solution. How much 8% solution should she add?

Answer 1

let the amount of the 8% solution she must add be x ml
.03(60) + .08x = .06(60+x)
times 100 ....
3(60) + 8x = 6(60+x)
180 + 8x = 360 + 6x
2x = 180
x = 90

She should add 90 ml of the stronger solution