In: Statistics and Probability
Suppose that a batch of 130 items actually contains 10 faulty items (but we don’t know which ones are faulty). A quality control officer gets to sample 5 items from the batch. If there is at least one faulty item in the sample, the whole batch is classified as faulty and sent back to the manufacturer (as it should be!). What is the chance that the quality control officer correctly detects this faulty batch of items?