Question

In controlling the quality of mass-produced glass bricks, the probability that an inspector will catch one which is cracked is 0.005, the probability that he will catch one with air bubbles is 0.003, the probability that he will catch one with discoloration is 0.003, the probability that he will catch one which has an air bubble and is cracked is 0.0007, the probability that he will catch one which is cracked and discolored is 0.0005, the probability that he will catch one which has air bubbles and is discolored is 0.0004, and the probability that he will catch one with all three of these imperfections is 0.0001. What is the probability that he will catch a glass brick with at least one of these imperfections?

Answer 1