How to calculate percentage - Step-by-step guide
Calculating a percentage involves finding out how much one quantity is in relation to another quantity, expressed as a fraction of 100.
Could also be formulated as finding the proportion that a certain value represents out of a total value, and then expressing that proportion as a fraction of 100.
Step-by-step guide on how to calculate a percentage:
Step 1: Identify the Part and the Whole Identify the two quantities you're working with: the part you want to express as a percentage and the whole from which it is a part.
Step 2: Set Up the Percentage Formula Use the formula:
Percentage (%) = (Part / Whole) × 100
Step 3: Divide the Part by the Whole Divide the value of the part by the value of the whole.
Step 4: Multiply by 100 After dividing, multiply the result by 100 to convert the decimal or fraction into a percentage.
Step 5: Express as a Percentage The result of the multiplication is the percentage you're looking for. Add the "%" symbol to indicate that it's a percentage.
Here's an example:
Example: Calculating 20% of 150
Step 1: Identify the Part and the Whole Part = ? (We're trying to find 20% of something) Whole = 150
Step 2: Set Up the Percentage Formula Percentage (%) = (Part / Whole) × 100
Step 3: Divide the Part by the Whole We're trying to find 20% of 150, so the part is 20% and the whole is 150. Part = 0.20 (20% as a decimal) Whole = 150
Step 4: Multiply by 100 Multiply 0.20 by 100: 0.20 × 100 = 20
Step 5: Express as a Percentage The result is 20, so 20% of 150 is 20.
Therefore, 20% of 150 is 30.
Example Percentage Problem Calcualtion:
You want to calculate the percentage of students who passed an exam. Out of 80 students, 65 passed.
Solution:
- Part (Number of Students Who Passed): 65
- Whole (Total Number of Students): 80
- Fractional Proportion: 65 / 80 ≈ 0.8125
- Percentage: 0.8125 × 100 ≈ 81.25%
So, approximately 81.25% of the students passed the exam.
