Question

Find how many quarts of 5% butterfat milk and 2% butterfat milk should be mixed to yield 45 quarts of 3% butterfat milk.

The mixture should contain quarts of the 5% butterfat milk.

Answer 1

It would take 4 quarts of 5% buttermilk and 41 quarts of 2% buttermilk to make 45 quarts of 3% buttermilk.

Explanation:

Let the number of 5% quarts = x

Let the number of 2% quarts = y

x+y=45

y=45-x

(.05)x+(.02)y=(0.03)45

5x+2y=102

5x+2(45-x)=102

5x+90-2x=102

3x=12

x=4

y=45-x=45-4=41

So it would take 4 quarts of 5% buttermilk and 41 quarts of 2% buttermilk to make 45 quarts of 3% buttermilk.