Two trains 100 meters and 95 meters long respectively pass each other in 27 seconds when they run in the same direction and in 9 seconds when they run in opposite directions. Speed of the two trains are

Let speeds be v1 and v2 km/hr (v1 > v2 for same direction case). Same direction: relative speed = v1 - v2 = (100+95)/27 km/sec = 195/27 × 18/5 = 26 km/hr. Opposite direction: relative speed = v1 + v2 = (100+95)/9 km/sec = 195/9 × 18/5 = 78 km/hr. Solving v1 - v2 = 26 and v1 + v2 = 78 gives v1 = 52 km/hr and v2 = 26 km/hr. Therefore option B is correct.