Looking at the quantities you've penciled in, you can expect to see two matters: First, two of the squares have the exact same pair of quantities (and only those people two quantities), and 2nd, the four only seems the moment. Two of those squares are by now penciled in with a matching pair of 5 and 6, so we know we can do away with five and 6 as feasible options for the other bins. Box 6 requires a 4.