Question

In the lab, Keith has two solutions that contain alcohol and is mixing them with each other. He uses twice as much Solution A as Solution B. Solution A is 19% alcohol and Solution B is 14% alcohol. How many milliliters of Solution B does he use, if the resulting mixture has 156 milliliters of pure alcohol

Answer 1

Quantity of solution B required is 300 ml

Explanation:

Let "a" be quantity of solution A required

Let "b" be quantity of solution B required

We are given Solution A is 19% alcohol and Solution B is 14% alcohol and that the resulting mixture has 156 milliliters of pure alcohol

Thus;

0.19a + 0.14b = 156 - - - (eq 1)

Also, He uses twice as much Solution A as Solution B.

Thus;

a = 2b

Putting 2b for a in eq 1 gives;

0.19(2b) + 0.14b = 156

0.38b + 0.14b = 156

0.52b = 156

b = 156/0.52

b = 300 ml

Quantity of solution B required is 300 ml