Percentages

Percentages are an easy way to compare amounts. While it might be hard to see know whether 7 parts in 35 is more or less than 70 parts in 100 once you convert both to percentages it is easy to which is the largest. Percentages tell you how many parts per 100 there is - so if you have a t-shirt that is 100% cotton the shirt all cotton. If your t-shirt is 75% cotton and 25% nylon then 75 parts out of 100 are cotton to 25 parts nylon.