Subject: General Aptitude · Chapter: Problems on Trains · Exam: · Marks: · Difficulty:
A 180-metre long train crosses another 270-metre 53. A train overtakes two persons walking along a long train running in the opposite direction in 10.8 railway track. The first one walks at 4.5 km / hr. seconds. If the speed of the first train is 60 kmph, The other one walks at 5.4 km / hr. The train needs what is the speed of the second train in kmph? 8.4 and 8.5 seconds respectively to overtake them. (Bank P.O., 2010) What is the speed of the train if both the persons are walking in the same direction as the train?
(a)80 66 km / hr
(b)90 72 km / hr
(c)150 78 km / hr
(d)81 km / hr Cannot be determined
Answer
Answer (as printed): B
Explanation
Let the speed of the second train be x m/sec. Speed of the first train = 60 kmph 5 50 = 60 × m/sec. = m/sec. 18 3 50 Relative speed of the two trains = x + m/sec. 3 50 180 + 270 3 x + 50 4500 \ x+ = ⇔ = 3 10.8 3 108 4500 ⇔ 3 x + 50 = × 3 = 125 108 ⇔ 3x = 75 ⇔ x = 25. Hence, speed of second train = 25 m/sec 18 = 25 × kmph = 90 kmph. 5 120
Explanation as extracted from the printed page; notation may be imperfect.