# What is probability in Mathematics OR Explain how do you calculate probability ?

Whenever we're unsure about the outcome of an event, we can talk about the probabilities of certain outcomes — how likely they are. OR Many events can't be predicted with total certainty. The best we can say is how likely they are to happen, using the idea of probability.

Probability of an Event = Number of ways it can happen / Total number of outcomes

Let us understand, What is equally likely Events or outcomes? When tossing a coin, There are two possible outcomes of an experiment:
Probability of getting a Head is 1/2
Probability of getting a Tail is 1/2
We have seen in the experiment of tossing a coin that each of the outcome has the same chance of occurring.

When each of the outcome of the experiment has the same chance of occurring then we can say , the outcomes of the experiment are equally likely.

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