Conditional probability: GCSE Maths revision
Conditional probability is “given that”. Restrict the sample space to what you now know, then find the proportion of the remaining outcomes.
Given that
A card is drawn from 52. Given it is a heart, P(king)?
Try these questions
Cover the answers and have a go first. Worked solutions are underneath.
Bag: 4 red, 6 blue. One red is removed. P(second is red)?
P(A) = 0.5, P(A and B) = 0.2. P(B given A)?
Common mistakes
- Using the original total after you have been given extra information.
Answers and working
Frequently asked questions
Is this on Foundation?
Formal “given that” is Higher. Foundation still does without-replacement trees, which is the same idea.
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