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How to Calculate Percentages — Complete Guide
· Tags: percentage-calculator, math-guide, percent-formula, business-math
Basic Percentage Formulas
Percentage of a number: X × Y ÷ 100 = Result
Example: 15% of 200 = 200 × 15 ÷ 100 = 30
What percent is X of Y: X ÷ Y × 100 = Percentage
Example: 30 ÷ 200 × 100 = 15%
Percentage increase/decrease: X ± (X × Y ÷ 100) = Result
Real-World Applications
Percentages are everywhere: sales tax (8.5%), tips (15-20%), discounts (30% off), interest rates (5% APR), and statistical reports.