1. The problem statement, all variables and given/known data 1 and 2 take turns shooting at a target. Each time 1 shoots he hits the target with probability p1; 2 hits it with probability p2 each time. 1 shoots first. They stop when the target has been hit twice. What is the probability that... a) The first hit was by 1 ? b) Both hits were by 1? c)Both hits were by 2? 2. Relevant equations Conditional probability? 3. The attempt at a solution Actually I'm a little (very) rusty. I took probability a year ago, and I just don't know how to start it. I'm totally lost here. Would appreciate any help. Thanks, Roni.