P & C.


@cskrahul Always give answer while asking question

@cskrahul
Total number of stations where train is stopping = 4
Total number of stations where train is not stopping = 8So if we arrange all stations where train is not stopping linearly then there will be 9 positions to place 4 stations in between them
we need to choose 4 stations out of 9 options =
$9C_4$ = 126

OK got it