How do you convert between Magnetic North and Grid North?

The method for converting between Magnetic North and Grid North involves understanding the relationship defined by magnetic declination. The correct approach is to consider the magnetic declination value, which is the angle difference between True North (or Grid North) and Magnetic North. This value can be positive or negative depending on your geographic location, indicating whether Magnetic North is east or west of True North.

In the choice given, where it states to "Grid to Mag add, Mag to grid get rid of +-3 degrees," reflects a simplified way of expressing that conversions rely on respective additions or subtractions based on the magnetic declination. When converting from Grid North (True North) to Magnetic North, you would typically add the declination. Conversely, when converting Magnetic North back to Grid North, you would subtract the declination.

The indication of "get rid of +-3 degrees" suggests an understanding that the conversion does not simply rely on a fixed degree increment but rather on the actual declination that can vary across different locations and should always be confirmed from reliable navigational sources.

This option aligns with the general navigational principles used for the conversion between these two bearings, integrating the essential understanding of magnetic declination and its practical application in navigation.