Alcohol solution problem

Question

Fatuma needs to mix a 10% alcohol solution with a 40% alcohol solution to create 100 milliliters of a 19% solution. How many milliliters of each solution must Fatuma use?

Answer 1

Of course, Mark M. is correct.

It may be easier to see the answer if you work with 2 variables and 2 equations:

F + T = 100

.4F + .1T = .19*100

where F is the ml of 40% and T is the amount of 10%.

Answer 2

(0.10)(100 - x) + (0.40)(x) = (0.19)(100)