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Math Calculators

Solve percentages, fractions, statistics and geometry, with the working shown.

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About these calculators

From quick percentages to descriptive statistics, each math tool shows the formula and the intermediate numbers so you can check the working yourself.

Related guides

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How to calculate the square footage of a room

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Percentage change vs. percentage difference: which one should you use?

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Scientific notation explained: how to read, write and use it

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How to simplify fractions: three methods, from quick to foolproof

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How to calculate probability: the few rules that solve most problems

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How to calculate percentages: 3 formulas that solve almost everything

Nearly every percentage question is one of three types. Learn them, plus the mental shortcuts and traps that catch people out.

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Mean, median and mode: which "average" tells the truth?

The same numbers can give three very different averages. Here is how to calculate each one and when to trust which.

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