How to calculate percentage of an amount

Percentages are an essential part of everyday life, whether you’re calculating discounts while shopping, determining your grade in a class, or analyzing financial data. In this article, we will explore the concept of calculating the percentage of an amount and provide practical examples to help you understand this crucial skill.
Understanding Percentages
A percentage is a way of expressing a number as a fraction of 100. It is denoted using the ‘%’ sign. For example, when we say that someone scored 90% on a test, it means they achieved 90 out of every 100 possible points. Similarly, if an item is discounted by 20%, its price has been reduced by 20 out of every 100 units.
The Formula for Calculating Percentage
To calculate the percentage of an amount, you will need to use the following formula:
Percentage (P) = (Part (X) / Whole (Y)) * 100
In this formula:
– P represents the percentage
– X represents the part or portion you’re interested in
– Y represents the whole or total amount
Step-by-Step Guide on Calculating Percentage
Step 1: Identify the part and the whole
Before you can calculate the percentage, determine which value represents the part or portion and which value represents the whole or total amount.
Step 2: Divide the part by the whole
Take the part (X) and divide it by the whole (Y). This will give you a decimal value.
Step 3: Multiply by 100
To convert this decimal value into a percentage, multiply it by 100.
Step 4: Add the ‘%’ sign
Finally, add the ‘%’ sign to your result to express it as a percentage.
Examples
1.Calculating Discounts:
If an item originally costs $200 and there’s a 25% discount available, what’s the discount amount?
Here, the whole (Y) is the original price ($200) and the percentage (P) is the discount rate (25%). To calculate the new price:
Discount Amount (X) = (Percentage (P) / 100) * Whole (Y)
X = (25 / 100) * 200
X = 0.25 * 200
X = 50
The discount amount is $50.
2.Calculating Grades:
If a student scored 45 points out of a possible 60 points on an exam, what percentage did he achieve?
In this case, the part (X) is the scored points (45), and the whole (Y) is the maximum possible points (60).
Percentage (P) = (Part (X) / Whole (Y)) * 100
P = (45 / 60) * 100
P = 0.75 * 100
P = 75%
The student achieved a score of 75%.
In conclusion, understanding how to calculate percentages for various purposes can greatly increase your ability to make informed decisions. By following this simple formula and remembering these examples, you’ll be well-equipped to tackle any percentage-related problem life may throw at you!