Start here · Essential guide
Understanding Odds and Percentages
A plain-language overview of how chances are written as fractions, percentages and odds, how to compare them, and why the wording of a chance matters.
Chance and Probability
Odds and Percentages
Reading and converting odds, risk and percentages.
Combinations and Permutations in Plain English
Learn how counting arrangements and selections works, when order matters, and why the number of possible outcomes grows so quickly, using simple examples.
Compound Probability: Why Chances Multiply
See why the chance of several things all happening is found by multiplying, how fast it shrinks, and how to handle the chance of at least one success.
Converting Odds to Percentages Step by Step
Worked examples for turning odds into percentages and percentages back into odds, with simple formulas, checked arithmetic and common mistakes to avoid.
Odds vs Probability: Two Ways to Say the Same Thing
Understand how odds and probability describe the same chance in different ways, why the two are often confused, and how the formulas link them.
One in a Million: Making Sense of Tiny Probabilities
Use everyday comparisons like seconds, coin flips and dice to feel how small a one-in-a-million chance is, and why tiny probabilities are so easy to misjudge.
Percent Change vs Percentage Points
Learn the difference between a percent change and a change in percentage points, why reports mix them up, and how to calculate each correctly.
Reading Fractional, Decimal and American Odds
A numeracy guide to the three common odds notations, with checked conversions between them and to implied percentages. Not betting advice.
Relative Risk and Absolute Risk
Why a large relative change in a tiny risk can still be small in absolute terms, with checked examples and questions to ask when reading risk statistics.
Why Advertised Chances Can Mislead
How selective statistics, framing, rounding and missing context can make advertised chances look better than they are, and the questions that expose them.
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