Mathematics
What is Probability?
Probability is the branch of math that measures how likely an event is, on a scale from 0 (impossible) to 1 (certain). It's how we reason about chance, risk, and uncertainty.
See it, don’t just read it.
Watch a 2-minute lesson with voice + animation that explains probability.
Key things to understand
- 1When outcomes are equally likely, probability = favorable outcomes ÷ total outcomes.
- 2It ranges from 0 (never) to 1 (always); 0.5 means 50-50.
- 3Independent events' probabilities multiply (e.g., two coin flips).
- 4It underpins statistics, gambling odds, insurance, and machine learning.
Frequently asked questions
- How do you calculate simple probability?
- Divide the number of favorable outcomes by the total number of equally likely outcomes.
- What does a probability of 0.5 mean?
- A 50% chance — the event is as likely to happen as not, like a fair coin landing heads.
- What's the difference between probability and statistics?
- Probability predicts the chance of outcomes; statistics analyzes real data to draw conclusions.