The events A A\,A and B B\,B are such that P(A)=320\displaystyle P(A) = \frac{3}{20}P(A)=203, P(A∩B)=120\displaystyle P(A \cap B) = \frac{1}{20}P(A∩B)=201 and P(A∣B)=514\displaystyle P(A|B) = \frac{5}{14}P(A∣B)=145.
Find P(B)P(B)P(B).
Find P(A∪B)P(A \cup B)P(A∪B).
Find P(B∣A′)P(B|A')P(B∣A′).
Practise Edexcel A Level Maths Conditional Probability with exam-style questions for A Level Maths. 100 questions covering Set Notation, Conditional Probability, Conditional Probabilities in Venn Diagrams, Probability Formulae, and Tree Diagrams, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.