Calculating theoretical probabilities from two-way tables (two events)
I can calculate and use theoretical probabilities for combined events using two-way tables (2 events).
Calculating theoretical probabilities from two-way tables (two events)
I can calculate and use theoretical probabilities for combined events using two-way tables (2 events).
These resources will be removed by end of Summer Term 2025.
Lesson details
Key learning points
- The probability of an outcome can be found by considering a two-way table showing all possible outcomes for two events.
- The probability of a set of outcomes can be found using a two-way table showing all possible outcomes for two events.
- The probability of a set of outcomes can be found using a two-way table, even when the outcomes are not equally likely.
Keywords
Theoretical probability - A theoretical probability is a probability based on counting the number of desired outcomes from a sample space where all individual outcomes are equally likely.
Common misconception
Pupils may struggle with finding the probability of A or B, and may count the outcomes that belong to A and B twice.
If you use an example, such as visiting particular countries, ask the pupils how someone would respond to the question 'have you visited X or Y' if they have in fact visited both countries.
To help you plan your year 9 maths lesson on: Calculating theoretical probabilities from two-way tables (two events), download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 9 maths lesson on: Calculating theoretical probabilities from two-way tables (two events), download all teaching resources for free and adapt to suit your pupils' needs.
The starter quiz will activate and check your pupils' prior knowledge, with versions available both with and without answers in PDF format.
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The assessment exit quiz will test your pupils' understanding of the key learning points.
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Explore more key stage 3 maths lessons from the Probability: theoretical probabilities unit, dive into the full secondary maths curriculum, or learn more about lesson planning.
Licence
Starter quiz
6 Questions


Exit quiz
6 Questions





