You know that you can safely stand on the hang-over end of a heavy plank that rests on a table. How far depends on your mass and the mass of the plank. Suppose you can stand on the end of a plank that overhangs the edge of the supporting table 1/5 its total length. Then how massive is the plank compared to your mass?
a) 1 and 1/3 times
b) more than 1 and 1/3 times
c) 2/3
d) the same
e) 1/3