How Loan Repayments Are Calculated (EMI and Mortgages)
How the monthly payment on a loan or mortgage is worked out, why early payments are mostly interest, and how rate and term change the total.
Percentages & Fractions
9 guides.
Percentages When Shopping: Discounts, Tax and Tips
Work out sale prices, stacked discounts, VAT or sales tax (adding and removing it) and tips quickly, with the multiplier method.
Ratios and Proportions Made Simple
Simplify ratios, share an amount in a ratio, and solve proportions by cross-multiplying, with recipe and map examples.
Rounding and Significant Figures: Rules and Examples
How to round to decimal places, significant figures and the nearest 10, 100 or 1000, plus the rules for counting significant figures.
Scientific Notation (Standard Form) Explained
Write very large and very small numbers in scientific notation, convert back, and multiply and divide numbers in standard form.
Compound Interest Explained (with the Formula and Examples)
How compound interest works, the formula A = P(1 + r/n)^(nt), how compounding frequency changes the result, and the rule of 72.
How to Calculate a Percentage: 3 Easy Methods
Learn three simple ways to calculate a percentage of a number, find what percent one number is of another, and work out percentage change.
How to Find the LCM and GCF (Three Methods)
Find the least common multiple and greatest common factor by listing, prime factorisation and Euclid's algorithm, and learn when to use each.
How to Simplify Fractions Step by Step
Simplify any fraction to its lowest terms using the greatest common factor, with worked examples, prime-factor checks and common mistakes.