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Probability That Depends on Context

Part of Conditional Probability · GCSE GCSE Mathematics revision

This introduction covers Probability That Depends on Context within Conditional Probability for GCSE Mathematics. Revise Conditional Probability in Probability for GCSE Mathematics with 14 exam-style questions and 12 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 1 of 5 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 1 of 5

Practice

14 questions

Recall

12 flashcards

Probability That Depends on Context

What's the chance of rain if it's cloudy? What's the probability a student passes an exam if they've been attending classes regularly? These situations involve conditional probability - where the likelihood of one event depends on whether another event has already occurred.

Conditional probability helps us make better predictions by considering additional information.

Keep building this topic

Read this section alongside the surrounding pages in Conditional Probability. That gives you the full topic sequence instead of a single isolated revision point.

Key FactsCalculating Conditional ProbabilityExam Tips

Practice Questions for Conditional Probability

What does the notation P(A|B) mean?

  • A. The probability of A and B both occurring
  • B. The probability of A occurring given that B has already occurred
  • C. The probability of A or B occurring
  • D. The probability of A occurring divided by the probability of B occurring
1 markfoundation

P(A) = 0.4, P(B) = 0.3 and P(A ∩ B) = 0.12. Using conditional probability, determine whether A and B are independent events. You must show all your working and give a reason for your conclusion.

3 markshigher

Quick Recall Flashcards

What is conditional probability?
The probability of one event occurring given that another event has already occurred. It restricts the sample space to only the outcomes where the condition is met.
What does the vertical bar | mean in P(A|B)?
It means 'given that'. P(A|B) is read as 'the probability of A given B'. The event after the bar is the condition — it is already known to have occurred.

14 questions on Conditional Probability — practise free

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