Percentage is a concept we use in everyday life, from calculating discounts while shopping to understanding statistics in news reports. But what exactly is a percentage, and how do you calculate percentage? In this guide, we will break it down in the simplest way possible.
What is a Percentage?
A percentage is a way to express a number as a fraction of 100. The word “percent” means “per hundred.” For example, 50% means 50 out of 100, or half. Similarly, 25% means 25 out of 100, or one-fourth.
Basic Percentage Formula
To calculate a percentage, you can use the following formula:
Percentage = (Part / Whole) × 100
Here:
- Part is the portion of the total amount.
- Whole is the total value.
- Multiply by 100 to convert it into a percentage.
How to Calculate Percentage – Step-by-Step Guide
Let’s go through some common scenarios where you may need to calculate percentages.
1. Finding the Percentage of a Number
If you want to find what percentage a number represents out of a total, use this formula:
(Number / Total) × 100
Example:
You scored 45 marks out of 60 in a test. What is your percentage?
(45 / 60) × 100 = 75%
So, your score is 75%.
2. Finding a Percentage of a Given Number
Sometimes, you need to find a specific percentage of a number. In that case, use:
(Percentage × Total) / 100
Example:
What is 20% of 150?
(20 × 150) / 100 = 30
So, 20% of 150 is 30.
3. Converting a Percentage to a Number
If you have a percentage and need to find its equivalent value in a given amount, use:
(Percentage × Total) / 100
Example:
If a jacket is 30% off and the original price is $200, how much is the discount?
(30 × 200) / 100 = 60
So, the discount is $60.
4. Increasing a Number by a Percentage
To increase a number by a percentage, use:
New Value = Original Value + (Percentage × Original Value) / 100
Example:
A salary of $2,000 increases by 10%. What is the new salary?
New Salary = 2000 + (10 × 2000) / 100 = 2000 + 200 = $2,200
So, the new salary is $2,200.
5. Decreasing a Number by a Percentage
To decrease a number by a percentage, use:
New Value = Original Value – (Percentage × Original Value) / 100
Example:
A product costs $500, and there is a 15% discount. What is the new price?
New Price = 500 – (15 × 500) / 100 = 500 – 75 = $425
So, after a 15% discount, the price is $425.
6. Finding What Percentage One Number is of Another
If you need to find what percentage one number is of another, use:
(Smaller Number / Larger Number) × 100
Example:
What percentage is 25 out of 80?
(25 / 80) × 100 = 31.25%
So, 25 is 31.25% of 80.
Common Uses of Percentage in Real Life
- Shopping Discounts: Finding out how much you save during sales.
- Bank Interest Rates: Calculating interest earned on savings.
- Tax Calculation: Understanding how much tax is deducted.
- Exam Scores: Understanding your performance in tests.
- Fitness & Health: Calculating body fat percentage or calorie intake.
Quick Percentage Tricks
- 10% Trick: To find 10% of a number, move the decimal one place left.
- Example: 10% of 250 = 25
- 5% Trick: Find 10% first, then divide by 2.
- Example: 5% of 250 = 25 / 2 = 12.5
- 50% Trick: Divide by 2.
- Example: 50% of 80 = 40
- 25% Trick: Find 50% first, then divide by 2.
- Example: 25% of 80 = 40 / 2 = 20
Conclusion
Learning how to calculate percentages is an essential skill that helps in everyday decisions, from budgeting money to understanding statistics. With simple formulas and a bit of practice, you can easily master percentage calculations. If you want to explore more ways to calculate percentages, use our percentage calculator and try few problems on how to calculate percentage.