How to Calculate a Percentage: Part, Whole and Rate ↗
Learn how to calculate percentages using part, whole and rate, with worked examples, mental maths shortcuts and checks for common errors.
Learn the why
Guides
Clear explanations, formulas and practical examples for everyday percentage questions.
Percentage Change vs. Percentage Difference ↗
Understand when to use percentage change, symmetric difference or percentage points. Compare the same numbers with each formula.
Reverse Percentages: Find the Original Amount ↗
Work backwards from a discounted or increased amount. See reverse percentage examples and learn why adding a rate back can give the wrong answer.
Successive Percentage Changes and Stacked Discounts ↗
Calculate repeated increases and decreases using multipliers. Learn why stacked discounts do not add and equal percentage moves do not cancel out.
Marks to Percentage: Scores and Weighted Results ↗
Convert exam marks to a percentage and understand weighted scores. See examples, missing-mark checks and why averaging percentages can mislead.
Fractions, Decimals and Percentages: Conversion Guide ↗
Convert fractions, decimals and percentages with clear methods and a reference table. Learn repeating decimal rounding and percentages above 100.