By , 11 months ago

Look at the figure below. The situation is explained.

  
 Let the distance moved by platoon = x , when the last man reaches the first man.
Therefore the distance moved by man in this case = 50 + x
Let the speed of man = v_m   and the speed of platoon = v_p
Let the distance moved by platoon when the man comes back = y
 so distance moved by man in this case = 50 - y
So total distance moved by platoon = x + y = 50 , so y = 50 - x
  so 50 - y = x
Now the when the man moves to the first man , then
  (50+x)/ v_m =  x/v_p  (1)
 When the man comes back , then
  x/ v_m = (50-x)/ v_p  (2)
Divide (1) by (2)
 (50+x)/x =  x/(50 - x)
 So X=35.355 meters
 Total distance moved by man = 50+x + 50 - y = 2x + 50
                                                                          = 120. 71