This is a plotting type problem and as Mad Jock says you should be using a pair of dividers. You are using the fact that anywhere on Earth 1 degree of latitude (measured up the meridian of longitude) is 60 nm and 1 minute is 1 nm.
I personally would set my dividers to say 5 degrees = 300 nm and step from INGO to SUM. You would get a full 5 degrees, then close the dividers to SUM then measure the difference - much easier shown than described.
NB. This is not a departure problem and unless you are using proper spherical trigs (not a JAA requirement) then you will only get an approximate and probably wrong answer.
Last edited by RichardH; 24th Jun 2012 at 09:04.