22 Oct '12 15:30

... spread out along a one-metre line. You don't know how many but there is at least one. At time t=0 they all start moving along the line at 1 m/min. Some move in one direction, some in the other. When 2 ants meet they instantaneously turn and move in the opposite direction at 1 m/min. When an ant gets to the end of the line it also instantaneously turns and moves off at 1 m/min. There is an ant an the centre point of the line at t=0.

(a) Prove that there must be an ant at the centre point at t=1 min.

(b) what are the necessary and sufficient conditions for this ant to be the same one that was at the centre at t=0.

(a) Prove that there must be an ant at the centre point at t=1 min.

(b) what are the necessary and sufficient conditions for this ant to be the same one that was at the centre at t=0.