Guides
Plain-language explanations with real numbers, to go with our calculators.
How to Lower Your Loan EMI (and What It Really Costs)Five practical ways to reduce your monthly loan payment, with real numbers showing what each choice does to the total you pay.What BMI Does and Does Not Tell YouA plain explanation of Body Mass Index: how it is calculated, what the categories mean, and where it can mislead.How to Calculate Percentages in Your HeadSimple mental tricks for working out 10%, 15%, 20%, 25% and any other percentage without a calculator.How to Work Out a Sale Discount QuicklyFind the sale price in seconds, and learn why two discounts never simply add together.How Much to Tip and How to Split a Bill FairlyTipping basics, a fast mental method for 15% and 20%, and simple ways to split a bill.How Compound Interest Works, With Real NumbersA clear explanation of compound interest and why starting early matters, using worked figures.How to Calculate Percentage Increase and DecreaseThe simple formula for percentage change, plus why a rise and a fall of the same percentage do not cancel out.How to Work Out the Fuel Cost of a TripA simple way to estimate what a drive will cost in fuel, and how to save on it.How to Convert Celsius and Fahrenheit in Your HeadQuick mental shortcuts for switching between °C and °F, with the exact formulas and key temperatures.Miles to Kilometers: Easy Mental MathsHow to convert miles to kilometres and back without a calculator, with the exact factor.How to Count the Days Between Two DatesHow to work out the number of days between two dates, and whether to include the start and end day.
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