48 people were asked if they like tea, coffee and hot chocolate. Every person liked at least one of the drinks. 9 of the people like all three drinks. 28 of the people like hot chocolate. 30 of the people like tea. 19 of the people like tea and coffee. 6 of the people like tea and hot chocolate but not coffee. 2 of the people like coffee and hot chocolate but not tea.
Two of the 48 people are chosen at random. Work out the probability that they both like coffee.
72 exam-style questions on OCR GCSE Maths Conditional Probability. Each one has a worked solution and a mark scheme showing where the marks go.