We’ll walk you through the process of calculating percentages step-by-step, and show you how to do it in your head, too. Whether you need to calculate a tip at a restaurant or figure out your grade in a class, being able to calculate percentages is a very useful skill. So let’s get started with how do you get percentage!
What is a percentage?
A percentage is simply a number or ratio expressed as a fraction of 100. For example, 55% (pronounced “fifty-five percent”) is equal to the fraction or the ratio. In this guide, we’ll focus on proportions, which are two numbers that express how much larger one number is compared to the other.
We write proportions using the division symbol ( ÷ ), like this: The number on the left is called the antecedent, and the number on the right is called the consequent. So in our proportion above, 3 is the antecedent, and 2 is the consequent.
How to calculate percentages
Here’s an example of how to calculate a percentage:
What percent of people surveyed said they liked cookies?
- Convert the percentage into a decimal by removing the percent sign and moving the decimal point two places to the left.
- Next, multiply this decimal by the numerator (top number) of your proportion. So our equation now looks like this: Then divide your new numerator () by the new denominator (4), which in our case would equal.
- Finally, convert this into a percentage by multiplying by and adding the percent sign ().
We find that 80% of people who responded to our survey said they liked cookies. You can also use mental math to your advantage when calculating percentages without having to write anything down.
Another example to consider
Let’s look at another example where we’ll convert a percentage into a decimal and then solve for an unknown number:
What is 15% of 80?
- Start by converting 15% into its decimal equivalent. Now, all we have left to do is set up our proportion using what we know.
- From here, it’s just a simple matter of solving for x–cross multiplying and then dividing both sides by 3–to find thatx=60. Therefore 15% of 80 equals 60. And that’s all there is to it!
Just remember when you’re dealing with percents to really think about what they mean: per hundred, or out of one hundred– whether you’re finding what fractional part one number is of another or converting back and forth between percents, decimals, and fractions.
The tips and tricks at a glance:
1. Remove the percent sign and move the decimal two places to the left to convert the percentage to a decimal. 50%, for instance, becomes 0.50.
2. To obtain the part, multiply the decimal by the total. In this case, 0.50 x 100 equals 50..
3. To calculate what percentage one number is of another, divide the first number by the second number and then multiply that answer by 100%. In our example, 50 ÷ 100 = 0.50 x 100 = 50%.
Conclusion:
Being able to calculate percentages comes in handy in many everyday situations. Whether you’re trying to figure out how much tip to leave at a restaurant or want to know what grade you need on your final exam to get an A in class, being able to calculate percentages will help you get there quickly and easily.