A breathalyzer test is used by police in an area to determine whether a driver's blood alcohol content (BAC) is above the legal limit. The device is not totally reliable: 5.8% of drivers who have not consumed too much alcohol give a BAC reading from the breathalyzer as being above the legal limit, while 10.7% of drivers who have consumed too much alcohol will give a BAC reading below that level. Suppose that in fact, 6.9% of drivers are above the legal alcohol limit, and the police stop a driver at random.