SSC CPO 2023 PYQ — Question 139

The correct answer is option 2 i.e. 61.2.

The length of the train = 180 m

The length of the tunnel = 500 m

Time taken to cross the tunnel = 40 seconds

Speed of train = (Length of train + Length of tunnel)/Time

Total distance = Length of train + Length of tunnel = 180 + 500 = 680 m

Speed of train = $Distance \over Time$ = $680\over 40$ m/sec = 17 m/sec

Speed of train in km/hr = Speed of train in m/sec × $18\over 5$= 17 × $18\over 5$ = 61.2 km/hr

Hence the speed of train is 61.2 km/hr.