Use Probability to Predict How Often an Event Will Occur

Probability is usually written as a fraction and can be used to predict the number of times an event will happen when an experiment is carried out a large number of times.

Example 1

The probability of throwing tails on a coin is 1/2.

If we throw the coin 1,200 times, we can predict that there will be roughly 1/2 x 1,200 = 600 tails.

Example 2

The probability of throwing a 4 or 5 on a die is 1/3.

In 600 throws, we can predict that there will be roughly 1/3 x 600 = 200 fours or fives thrown.

Does that make sense?

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