When you're looking for a percentage,the best thing to do is to find out what the percentage is, is to divide the number that you're looking for (9), by the percentage that you have (84), and you then have to multiply this by 100 (as the total percent is 100).
9/84= 0.1071, and then 0.1071x100=10.71
Therefore, 9 is 10.71% of 84
Hope this helps :)
Edward III of England created the first English dukedom by naming his eldest son Edward, the Black Prince, as Duke of Cornwall in 1337, after he lost his own title of Duke of Normandy.