- We have four boxes. Box 1 contains 2000 components of which 5% are defective. Box 2 contains 500 components of which 40% are defective. Box 3 and 4 contains 1000 each with 10% defective. We select at random one of the boxes and we remove at random a single component. a) What is the probability that the selected component is defective? The space of this experiment consists of 4000 good (g) components and 500 defective (d) components arranged as follows: Box 1: 1900g, 100d Box 3: 900g, 100d Box 2: 300g, 200d Box 4: 900g, 100d b) We examine the selected component and we find it defective. On the basis of this evidence, we want to determine the probability that it came from box 2