# Maths KS3 / GCSE: Probability

This short film uses weather as an example to reflect how the concept of probability is used and applied.

The presenter describes the frequency of a weather event occurring and the fact that probabilities add up to 1.

So if we know the probability of an event occurring, then by subtracting from 1, we can calculate the probability of the event NOT occurring.

The video progresses on to show a structured way of calculating multiple events by using a â€˜Tree Diagramâ€™.

This is from the series: Real Life Maths

### Teacher Notes

The video clip could be used in a variety of ways to support learning. Teachers could play the video in class and the learners fill in a worksheet based on the video, followed by exam questions.

Learners in pairs rate each scenario on a probability scale by using words such as impossible, even chance more/less likely and certain.

The video can be used to reinforce and establish key skills as part of a carousel lesson where students in groups of 3 or less depending on class numbers rotate and answer key questions based on the video clip.

The video could also be used as a peg to investigating probability in a casino for example, to work out chances of winning/losing. To calculate fairness in gaming.

### Curriculum Notes

This clip will be relevant for teaching Maths at KS3/GCSE in England Wales and Northern Ireland. Also at National 4, 5 and Higher in Scotland.

This topic appears in OCR, Edexcel, AQA, WJEC in England and Wales, CCEA GCSE in Northern Ireland and SQA in Scotland.