Question

Doctor Brilliantstein created a human-like creature with two legs that each have a roughly rectangular cross-section. She wants to improve her creation so that its legs can support as much weight as possible. She has two ideas:

Double the number of legs.
Keep the two legs but double the length and width of their cross-sections.
Which improvement should she choose?

Answer 1

Step-by-step explanation:

Let the cross-section of rectangular shaped legs have one side called as length be x

and other side called as breadth be y

So now the area of the cross-section = xy

For 4 legs = 4xy -------( option a)

Next, if x becomes 2x and y becomes 2y then area of one leg = 4xy

and for 2 legs = 8xy ------ (option b)

since 8xy > 4xy so she must go with option b .