Question 1
Paper 1, no calculatorMedium7 marksA probability tree models the results of a medical study of a risk factor and a disease A person is selected at random from the population. The probabilities on the second set of branches are conditional on the outcome at the first set of branches.
Find the probability that a randomly selected person has both and
Hence determine the probability that a randomly selected person has
Hence determine the probability that a person has given that they have Give your answer exactly, and state whether more than half of the people with have