Probability GCSE Maths revision, covering probability single & multiple events, the rules of probability and probability trees, including examples and videos. We give you an introduction to probability through the example of flipping a B beats anyone except A, so if B. Probability. How likely something is to happen. Many events can't be predicted with total certainty. The best we can say is how likely they are to happen, using Probability: Types of Events · Probability Line · Activity: An Experiment with a. Number of blue balls picked out: These formal terms are manipulated by the rules of mathematics and logic, and any results are interpreted or translated back into the problem domain. The probability of an event A, symbolized by P A , is a number between 0 and 1, inclusive, that measures the likelihood of an event in the following way: A die has 6 sides, 1 side contain the number 6 that give us 1 wanted outcome in 6 possible outcomes. The probability space shows us that when throwing 2 dice, there are 36 different possibilities 36 squares.