A box contains 7 fiction books, 5 non-fiction books, and 3 biographies. Two books are selected from the box at random without replacement.
Draw a tree diagram to represent this information.
Find the probability that the two books selected are both biographies.
Given that at least one of the books selected is non-fiction, find the probability that both books are non-fiction.
24 exam-style questions on Edexcel A Level Maths 2.5 Tree Diagrams. Each one has a worked solution and a mark scheme showing where the marks go.