Knowing how to calculate percentages will help you not only score well on a math test but in the real world as well. You can work out percentages to calculate how much to tip at restaurants, find the percent change of a price, or even determine statistics of your favorite sports team. While the language may initially seem confusing, calculating percentages can actually be quite easy.

Search for evidence. Before you believe something or make a decision, make sure you have done ample searching for evidence to back it up. Don’t just believe something because your friend told you it’s true, but spend time researching the situation on reliable sources on the Internet, checking it out at your local library, or talking to experts in the field to find out whether it’s true.

A percentage tells you how many things you would have if you had 100 total. For example, say 25% of your apple harvest is always spoiled. That means for every 100 apples you harvest, 25 of them will be spoiled, or 25/100. Converting fractions allows you to find percentages in the real world, such as what percentage of apples is spoiled if you get 450 bad apples out of 2,500.

To calculate a ratio, start by determining which 2 quantities are being compared to each other. For example, if you wanted to know the ratio of girls to boys in a class where there are 5 girls and 10 boys, 5 and 10 would be the quantities you're comparing. Then, put a colon or the word "to" between the numbers to express them as a ratio. In ...