Conditional probability in a Venn diagram
I can calculate a conditional probability from a Venn diagram.
Conditional probability in a Venn diagram
I can calculate a conditional probability from a Venn diagram.
These resources will be removed by end of Summer Term 2025.
Lesson details
Key learning points
- A Venn diagram can be used to calculate conditional probabilities
- A Venn diagram can be used to calculate conditional probabilities involving sets of events
- Venn diagrams allow us to identify which events are mutually exclusive
- Venn diagrams can be used to identify which events are independent
Keywords
Venn diagram - Venn diagrams are a representation used to model statistical/probability questions. Commonly circles are used to represent events.
Probability - The probability that an event will occur is the proportion of times the event is expected to happen in a suitably large experiment.
Conditional probability - Conditional probability is the probability of an outcome occurring given that another event has occurred.
Independent events - Event A is independent of event B if the probability of event A occurring is not affected by whether or not event B occurs.
Mutually exclusive - Mutually exclusive events have no outcomes in common.
Common misconception
Pupils may confuse the probability of event A given B, P(A|B), with the probability of event A and B occurring.
Use the context of the question to make a judgement about what probability is to be calculated. Try to avoid using, or draw attention to, potentially ambiguous language/notation. E.g. Is P(AB) referring to P(A given B) or P(B given A) or P(A and B)?
To help you plan your year 11 maths lesson on: Conditional probability in a Venn diagram, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your year 11 maths lesson on: Conditional probability in a Venn diagram, 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 4 maths lessons from the Conditional probability unit, dive into the full secondary maths curriculum, or learn more about lesson planning.
Licence
Starter quiz
6 Questions

P(blue) -
$$27\over 60$$
P(green) -
$$33\over 60$$
P(blue and has no swirl) -
$$12\over 60$$
P(blue given it has no swirl) -
$$12\over 27$$
P(green and has a swirl) -
$$18\over60$$
P(green given it has swirl) -
$$18\over 33$$

Exit quiz
6 Questions




