As you've stated an "airspeed" of 200 knots, I can't tell whether you're referring to IAS or TAS. If the former, you need to account for altitude and temperature to derive a TAS.
Just for the hell of it though, I ran some calculations based on Pans Ops criteria for 200 KIAS, ISA +15, at various altitudes and came up with the following :-
2000 feet : 0.655 NM
4000 feet : 0.693 NM
6000 feet : 0.738 NM
8000 feet : 0.785 NM
10000 feet : 0.840 NM
These values would be used in procedure design, though I feel sure that a bank angle of 45 degrees would never be used in an instrument procedure design. Indeed, I'm not even sure that the forumula is totally accurate at that sort of bank angle.