Answer:
10 quarts of 5% with 20 quarts of 2% buttermilk
Explanation:
x + y = 30 where x = volume of 5% and y = volume of 3%
0.05x + 0.02x = 0.03(x + y)
0.02x - 0.01y = 0 Multiply through by 100
2x - y = 0
Add the above equation to the first equation:-
3x = 30
x = 10
so y = 30-10 = 20