Start by converting 5 nm/cm at the Equator into nm/inch
There are approximately 2.54 cm in an inch so multiplying 5 nm by 2.54 gives 12.7 nm/inch at the Equator.
Then use the following equation to calculate the distance per inch at 44 degree latitude.
Distance at B = ( Distance at A x Cos B) / Cos A
Where A and B are latitudes.
Using A = 0 latitude at the Equator and B = 44 degrees latitude we have
Distance at 44 degrees = (12.7 nm x Cos 44) / Cos 0
Distance at 44 degrees = 9.14 nm
So the scale at 44 degrees is 9.14 nm/inch