Question 374252
0.04x + 0.01(60-x) = 0.02*60
0.04x + 0.6 - 0.01x = 1.2,
0.03x = 0.6,
x = 20 quarts, the amount of 4% butterfat milk, and 
60 - 20 = 40 quarts, the amount of 2% butterfat milk.