Students can go through AP Board 9th Class Maths Notes Chapter 14 Probability to understand and remember the concepts easily.

## AP State Board Syllabus 9th Class Maths Notes Chapter 14 Probability

→ If in an experiment all the possible outcomes are known in advance and none of the outcomes can be predicted with certainty, then such an experiment is called a random experiment.

Eg: Tossing a coin; throwing a die, drawing a card from deck of cards.

→ The possible outcomes of a trial are called events.

→ Events are said to be equally likely if there is no reason to expect any one in preference to other. Thus equally likely events mean outcome is as likely to occur as any other outcome.

→ To measure the chance of its happening numerically we classify them as follows.

→ Certain: Something that must happen

→ More likely: Something that would occur with great chance

→ Equally likely: Something that have the same chance of occurring

→ Less likely: Something that would occur with less chance

→ Impossible: Something that cannot happen

→ Probability of an event = \(\frac{\text { Number of favourable outcomes for the event }}{\text { Number of total possible outcomes }}\)