What is the math equation that give us 2 percent milk from

To make 2% milk from whole milk, you need to mix whole milk with skim milk. The formula for calculating the amount of skim milk needed is:

```

Skim milk (gallons) = (Total milk gallons) - (Whole milk gallons)

```

For example, if you want to make 1 gallon of 2% milk from whole milk, you would need to mix 0.98 gallons of whole milk with 0.02 gallons of skim milk.