Year 11 - Maths
Conditional probability in a Venn diagram
Conditional probability
Study Hub
Study Guides
This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit, pupils use their knowledge of calculating theoretical probabilities and extend it to calculate conditional probabilities.
Lesson Summary
You will learn to calculate a conditional probability from a Venn diagram.
Key Notes
- 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
Vocabulary To Learn
- 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 Mistakes To Avoid
- Pupils may confuse the probability of event A given B, P(A|B), with the probability of event A and B occurring.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
A Venn diagram can be used to calculate conditional probabilities. A Venn diagram can be used to calculate conditional probabilities involving sets of events.
2. Use this key word in a maths sentence and explain it clearly. 'Venn diagram'
Venn diagrams are a representation used to model statistical/probability questions. Commonly circles are used to represent events. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: Pupils may confuse the probability of event A given B, P(A|B), with the probability of event A and B occurring. Correction: 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)?
More Lessons In This Unit
- Advanced problem solving with conditional probability Study Guide
- Algebra in tree and Venn diagrams Study Guide
- Checking and securing calculating probabilities from diagrams Study Guide
- Checking and securing calculating probabilities from tables Study Guide
- Checking and securing displaying outcomes Study Guide
- Checking and securing exhaustive events Study Guide
- Combinations Study Guide
- Comparing multiple representations to calculate conditional probabilities Study Guide
- Conditional probability in a tree diagram Study Guide
- Conditional probability in a two-way table Study Guide
- Constructing three event Venn diagrams Study Guide
- Experimental probability Study Guide
- Experimental vs theoretical probability Study Guide
- Frequency trees Study Guide
- Probabilities in three event Venn diagrams Study Guide
- Probabilities involving algebra Study Guide
- Problem solving with conditional probability Study Guide
- Set notation Study Guide
Browse all guides in the Year 11 Maths guide library.