How Many Locs I Need For UnderCut

My hair is shaved on the sides and back, what number of locs will I want for a total head of locs?
For shaved hairdos (mohawk/undercut/high top Fade), these are the typical sums expected to provide you with a total head of locs.

width 0.75cm (50-60 Locs )

width 0.5cm locs (40-70 Locs)