- Enter the number of gallons into your calculator. In this example we will use 250 gallons.
- Press the multiplication key, then enter 8.34. This is the weight of a gallon of water, which has a specific gravity of 1.0.
- Press the key with the equal sign. Your equation so far should look like this: 250 x 8.34 = 2085.
- Press the multiplication key and enter 0.87 (the specific gravity of No. 2 fuel oil). Press the key with the equal sign again and you will have the weight of your fuel oil. Your equation at this point is: 2085 x 0.87 = 17388.9.

## Things You Will Need

- Calculator

## Tip

- To simplify this equation: (gallons x 8.34) x 0.87 = weight