Question

Find how many quarts of 5% butterfat milk and 2% butterfat milk should be mixed to yield 90 quarts of 3% butterfat milk.

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

Answer 1

• The mixture should contain 30 quarts of the 5% butterfat milk.

Explanation:

Let the required amount of 5% milk is x quartz, then the amount of 2% milk is 90 - x quartz.

Set equation for the fat content:

• 5% of x + 2% of (90 - x) = 3% of 90

• 0,05x + 0.02(90 - x) = 0.03*90
• 0.05x + 1.8 - 0.02x = 2.7
• 0.03x = 2.7 - 1.8
• 0.03x = 0.9
• x = 0.9/0.03
• x = 30