Question

100 ants (zero-length points) walk on a meter stick (a line) at 1 cm/second. When two ants collide, they both reverse direction. If an ant reaches the end of the stick, it falls off. What arrangement of ants maximizes the time before all ants have fallen off? How long can they last?

Answer 1

100 seconds

Answer 2

how? @ ktklown.

Answer 3

This is hurting my head to picture :/

Answer 4

pretend the ants just walk past each other instead of both changing direction; the result will be identical. in this model they would, at most, just walk from one end to the other which takes 100 seconds (1 meter at 1 cm/second).