Twelve impact wrenches are to be divided evenly among three assembly lines, four of the wrenches are used, the rest wrenches are new. What is the probability that line A (a particular line) gets two used wrenches?

3. The chance of contacting strep throat when coming into contact with an infected person is estimated as 0.15. Suppose the four children of a family come into contact with an infected person. Design and conduct a simulation to answer the following questions. Begin on Line 115 and conduct 10 trials. a) Estimate the average number of children who will get the disease. b) What is the probability of two of the children getting the disease? c) What is the probability of at least two of the children getting the disease?

7. An assembly line has two inspectors. The probability that the first inspector will miss a defective item is 0.05. If the defective item passes the first inspector, the probability that the second inspector will miss it is 0.01. What is the probability that a defective item will pass by both inspectors?

5. A bag contains 20 purple marbles, 15 red marbles, and 5 blue marbles. What is the probability of randomly selecting a purple marble, not putting it back, and then randomly selecting a blue marble? (Express your answer as a decimal rounded to two places.)