1. The problem statement, all variables and given/known data ******* SOLVED ********* There are three magazines A,B and C respectively. A survey of readers was taken and the following data was collected. 0.6 Read A 0.5 Read B 0.5 Read C 0.3 Read A&B 0.2 Read B&C 0.3 Read A&C 0.1 Read A&B&C What is the probability that a reader reads two magazines exactly? 2. Relevant equations P(R|Q) = P(Q n R) / P(Q) = probability of R given Q. where R,Q are events. 3. The attempt at a solution I attempted this by just using logic. I thought that readers who read A&B,B&C,A&C but not all three magazines would be the solution: giving a probability of 0.5 which I believe is correct. I assume conditional probability is meant to be used in the solution but I am unable to see how the sums fit. Any help would be much appreciated.