1000+ Train Problems Aptitude with Answers - 1

Ans: C

Speed of first train = $${120} / {10}$$ = 12 m/s

Speed of second train = $${120} / {15}$$ = 8 m/s

Let t sec be the time in which they cross each other

∴ t = $${Total length of trains} /{Relative speed of trains }$$ = $${120 + 120} / {(12 + 8)}$$ = $${240} / {20}$$ = 12 sec.

Ans: C

Relative speed of faster train w.r.t slower train

= 72 - 54 = 18 km/hr = $$18 × {5}/ {18}$$m/s = 5 m/s

Time taken by the faster train to cross the slower train

= $${100 + 120} /{5}$$ = 44 sec.

Ans: A

To pass the telegraph post, the train should cover its own length.

∴ Speed of train = 36 km/h = $$36 × {5}/{18}$$ = 10 m/s.

Required time = $${Length of train} / {Speed}$$ = $${100} / {10}$$ = 10 seconds.

Ans: C

Relative speed = (50 - 30) km/h = $$20 × {5}/{18}$$ = $${50}/{9}$$ m/s

Distance covered in 18 seconds at this speed = $${50}/{9} × 18$$ = 100 m

∴ Length of faster train = 100 m.

Ans: C

Speed of train = 120 km/hr = $$120 × {5}/{18} $$ = $${100} / {3}$$m/s

Time taken by train to cross a platform

= $${Length of train + Length of platform} / {Speed of train}$$

= $${120 + 130} / {100 / 3}$$ = $${250 × 3} / {100}$$ = $$7{1}/{2}$$sec.