How to Calculate Percentage: Step-by-Step Guide
Calculating percentages is an essential daily math skill for retail shopping discounts, test grades, financial tips, and business growth rates.
Step 1: Understand What Percentage Means
"Percent" comes from the Latin per centum, meaning "by the hundred." A percentage is simply a ratio expressed as a fraction of 100.
Step 2: Find the Percentage of a Given Number
To find X% of Y:
- Convert the percentage X into a decimal by dividing by 100 (e.g., 20% → 0.20).
- Multiply the decimal by the target number Y.
Example: What is 20% of $150?
0.20 × 150 = $30
Step 3: Calculate Percentage Off (Discount)
If an item originally costs $80 and has a 25% discount:
- Calculate discount amount: 0.25 × 80 = $20
- Subtract discount from original price: 80 - 20 = $60 final price