SSC CPO 2023 PYQ — Question 124

The correct answer is option 1 i.e. 72 km/h

Length of goods train = 350 m

Length of tunnel = 1250 m

Time taken by train to cross the tunnel = 80 sec

Speed = total distance/total time

Total distance = 1250 + 350 = 1600 m

Total time = 80 seconds

Speed (in m/s) = $1600\over 80$ = 20 m/s

Speed (in km/h) = 20 × $18\over 5$ = 72 km/h

Hence the speed of the train is 72 km/h.