The ratio (by volume) of salt and sugar in a certain mixture is 4 to 8. if the total volume of the solution is 300 cubic feet, what is the volume of sugar in the mixture?

You will use the ratio 4:8 to create a part to part to whole ratio.

First simplify 4:8 to 1:2, then make it 1:2:3 (Salt:Sugar:Total).

Use this to find the volume of sugar.  2 sugars for every 3 total would be equivalent to 200 cubic feet of sugar for every 300 total cubic feet.