Probability and the probability scale
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Probability is about estimating or calculating how likely or probable something is to happen. Probabilities can be described in words. For example, the chance of an event happening could be ‘certain’, ‘impossible’ or ‘likely’.
In maths, probabilities are usually written as A fraction is a part of a whole, for example 1/2. or A number that uses powers of 10 as place value. In the example of 0.82, the 8 represents tenths and the 2 represents hundredths. between 0 and 1, or A proportion representing parts per hundred, for example 9% is 9 out of 100, or 9/100. between 0% and 100%.
The probability scale
An event which is impossible has a probability of 0 and an event which is certain has a probability of 1. This means probabilities cannot be bigger than 1. This can be shown on a probability scale.
