Probability
Probability is the branch of mathematics that measures the chance of an event happening. It is expressed as a number between 0 and 1. A probability of 0 means the event is impossible. A probability of 1 means the event is certain to happen. For example, the probability of the sun rising tomorrow is 1. The probability of a human jumping to the moon without help is 0. Most things in life fall somewhere in between these two numbers. In exams, we often calculate this using a simple fraction.
This is the simplest form of probability. It assumes all outcomes are equally likely to happen. You divide the number of successful outcomes by the total number of possible outcomes. Example: Picking a King from a deck of cards.
This is the simplest form of probability. It assumes all outcomes are equally likely to happen. You divide the number of successful outcomes by the total number of possible outcomes. Example: Picking a King from a deck of cards. There are 4 Kings and 52 cards total. The probability is 4/52 or 1/13.
Ready to practice? Start an interactive lesson.
Start Lesson: Classical Probability