Stuck on vectors problem

I'm stuck on this vectors problem:
https://isaacphysics.org/questions/triangular_flying_num?board=26f7d632-feb0-46e9-a6e7-54ee72cbe608

My working:
For the plane going clockwise
Worked out the distance of one side of the triangle=198000m
The left side is d1, right side is d2 and the bottom side is d3.
v1=V-kV
v1=41.8

v2: I drew a tip to tail diagram with the vectors and the angle between two of them is 120 degrees so used the cosine rule and got v2=62.6517...
calculation: (V2)^2=(kV)^2+(V)^2-2(kV)(V)cos(120)

v3: did the same as v2, and got the same velocity

Total time=d1/v1 +d2/v2 +d3/v3
=11057s

For the plane going anticlockwise
v3: v3^2=(V)^2+(kV)^2-2(V)(kV)cos(60)
v3=49.73...

V2= did the same as v3 and got the same velocity

V1= V+kV
=68.1

Total Time=10870s

Difference in time= 187s

Why isn't this correct? I get this feeling I might've used vectors incorrectly