The Mathematics of Maybe: Introduction to Probability Mind Map

Chance and likelihood describe how possible an event is, using words such as certain, impossible, likely, unlikely, and equally likely.

Read the condition carefully and decide whether the event can happen, must happen, or may happen before assigning a probability idea.

The probability scale represents chance by numbers from 0 to 1, where 0 means impossible and 1 means certain.

After calculating, check whether your answer lies between 0 and 1. If not, the counting is wrong.

Experimental probability is the probability found from actual trials by dividing the number of times an event occurs by the total number of trials.

If the question says observed, recorded, surveyed, tossed many times, or experiment result, use the given data.

Theoretical probability is found by dividing the number of favourable outcomes by the total number of equally likely outcomes.

First list total equally likely outcomes, then count only the outcomes that satisfy the event.

Sample space is the set or list of all possible outcomes of a random experiment.

Write the sample space before solving probability questions where two conditions or two stages are involved.

An event is a selected part of the sample space, and its complement is the event that it does not happen.

When finding a complement, include every outcome that does not satisfy the event, including boundary values.

A tree diagram is a branching diagram used to list outcomes of a two-stage or multi-stage random experiment systematically.

Use a tree when an experiment has two actions, such as coin then die, two coins, or choosing then spinning.