Probability - EdexcelProbability and the probability scale
Probabilities can be written as fractions, decimals or percentages on a scale from 0 to 1. Knowing basic facts about equally likely outcomes can help to solve more complicated problems.
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 fractionA fraction is a part of a whole, for example 1/2. or decimalA 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 percentageA 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.