( CO 4 ) Ten rugby balls are randomly selected from the production line to see if their shape is correct Over time , the company has found that 89 4 % of all their rugby balls have the correct shape . If exactly ? of the 10 have the right shape , should the company stop the production line Yes , as the probability of seven having the correct shape is unusual No as the probability of seven having the correct shape is unusual Yes , as the probability of seven having the correct shape is not unusual No as the probability of seven having the correct shape is not unusual