If 18 defective glass bricks include 10 that have cracks but no discoloration, 5 that have discoloration but no cracks, and 3 that have cracks and discoloration, what is the probability that among 6 of the bricks (chosen at random for further checks) 3 will have cracks but no discoloration, 1 will have discoloration but no cracks, and 2 will have cracks and discoloration?