Answer:
Step-by-step explanation:
Let the speed of cyclist be C and bus be B.
Using the concept of relative speed:-
For incoming bus,speed = B + C
For overtaking bus,speed = B - C
Now,distance travelled b/w 2 incoming bus = (B + C)*4
Now,distance travelled b/w 2 overtaking bus = (B - C)*12
so,
(B + C)*4 = (B - C)*12
or, B=2C
Hence,distance b/w two buses in same direction,d=4*(3/2)B=6 B
Therefore, time gap=d/B=6 minutes