Unit price of olive oil: volume versus weight I am browsing olive oil on Google Shopping (the following problem also happens when I shop in local supermarkets). I found the information about unit price of olive oil is inconsistent. Sometimes only volume is available in liters and gallons, and sometimes it is weight in ounces and pounds. So I wonder how you can compare the unit prices between available information in volumes and weights? Do we have to know some common sense of the density of olive oil in order to convert between volume and weight using physics? Thanks!
According to this, a gallon of olive oil weighs 7.6 lbs.; 1l weighs .91kg.