Probability Probability is the likelihood of an even occurring. Outcomes are the possible results you can get from an event. Outcomes can be represented by a number or can be represented with numbers as a chance. An outcome can be likely, equally likely, unlikely, certain or impossible. Events that are certain mean there are no other possible outcomes. Impossible events have no chance of occurring. Equally likely events are when each outcome has exactly the same chance of happening. Events that are likely are not certain to happen but have a greater than 50/50 chance of happening. Unlikely events are not impossible but have a less than 50/50 chance of happening. Outcomes can also be described by chance. On a dice you have a 3 out of 6 chance of rolling an even number.