8/10 sounds pretty lucky
During this last engagement 2,876 shells were fired at the Bismarck. They are itemised as follows:
380 of 40.6 cm from Rodney339 of 35.6 cm from King George V527 of 20.3 cm from Norfolk254 of 20.3 cm from Dorsetshire716 of 15.2 cm from Rodney660 of 13.3 cm from King George V
It will never be known how many of them did actually hit (200, 300, maybe more?), but taking into account the short distances in the last phase of the action, it is assumed that many shells hit.