The apothem of a polygon, in this case a, can be found using the formula
Apothem=circumradius*cos(pi/sides)
Note in this problem, its a hexagon which makes the circumradius = to the side length since a regular hexagon can be split into 6 equilateral triangles.
a=47*cos(pi/6)=40.7 (approximation)
Hope it helped!
