Question

How many gallons of milk containing 5% butter fat must be mixed with 100 gallons of 1% milk to obtain 2% milk?

Answer 1

Let x = number of gallons of %5 milk
0.05x + 0.01(100) = 0.02(x+100)
0.05x + 1 = 0.02(x+100)
0.05x + 1 = 0.02x + 2
0.03x = 1
x = 33 and 1/3

Write back if you need more explanation