This is an old one mate! I won't give the answer away but as a clue for people, the trick is to work out how to get a '0' at the end and work backwards....not difficult using multiples of 8 :-)
This is an old one mate! I won't give the answer away but as a clue for people, the trick is to work out how to get a '0' at the end and work backwards....not difficult using multiples of 8 :-)