Question 365368
to make low-fat cottage cheese, milk containing 4% butterfat is mixed with
 milk containing 1% butterfat to obtain 15 gallons of a mixture containing 2%butterfat. 
How many gallons of each type of milk should be used?
Let x = amt of 4% milk required
then
(15-x) = amt of 1% milk required
:
A typical mixture equation:
.04x + .01(15-x) = .02(15)
solve for x