The events A A\,A and B B\,B are such that P(A)=14\displaystyle P(A) = \frac{1}{4}P(A)=41, P(A∩B)=110\displaystyle P(A \cap B) = \frac{1}{10}P(A∩B)=101 and P(A∣B)=25\displaystyle P(A|B) = \frac{2}{5}P(A∣B)=52.
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′).
29 exam-style questions on Edexcel A Level Maths 2.4 Probability Formulae. Each one has a worked solution and a mark scheme showing where the marks go.