To answer this question you will use ratios. The information given gives us a part to part ratio of 1 part vinegar for every 3 parts oil.
Because the total amount of furniture polish is 30 ounces, we will need to write one part vinegar to three parts oil as a part to part to whole ratio.
Use this information then and create an equivalent ratio with a total of 30 ounces. See below.
1 vinegar (x7.5) = 7.5 ounces
3 oil. (X7.5). = 22.5 ounces
4 total (x7.5). = 30 ounces
You will need 7.5 ounces of vinegar and a 22.5 ounces of oil.
