Best Online CAT Coaching

Counter to the first question, we should minimize the use of those hypotenuse walkways as they reduce the distance we travel.
The longest possible route would include then travelling through the edges of the rectangles and sqaures, and not touch any point more than once.
Best case scenario would be us touching each point exactly once.
This can be visualized as:

Where we do not use any of the hypotenuse and cross through each gate exactly once.
The total distance would be:
AH + HI + IP = 400 + 200 + 400 = 1000
DE + EL + LM = 400 + 200 + 400 = 1000
PO + JK + NM = 150 + 300 + 300 = 750
DC + FG + BA = 150 + 300 + 300 = 750
JO + KN = 400 + 400 = 800
CF + GB = 400 + 400 = 800
Adding up to: 5100 m
Therefore, 5100 is the correct answer.