Conditional probability

An airplane is missing. Based on its flight plan, it has been determined that the airplane is equally likely to be in any one of three locations. A search team will find the airplane in the ith location (assuming it is there) with probability pi = 1 − i/(i + 1), for i = 1, 2, 3. Find the conditional probability that the airplane is in the second (i = 2) location given that the airplane was not found while searching the first (i = 1) location