Question

A chemical company makes two brands of antifreeze. The first brand is 70% pure antifreeze, and the second brand is 95% pure antifreeze. In order to obtain 50 gallons of a mixture that contains 75% pure antifreeze, how many gallons of each brand of antifreeze must be used?

Answer 1

See below

Explanation:

Final amount of pure antifreeze = .75 (50)

amount of 70 % that is pure antifreeze = .70 x

amount of 95 % that is pure antifreeze = .95 (50-x)

ingredients in = ingredients out

.70x + .95 (50-x) = .75 (50)

x = 40 gal this is the amount of 70 %

then 95 % = 50 - 40 = 10 gal