A) 2:1 | B) 3:2 |

C) 4:3 | D) 5:4 |

Explanation:

Note : If two trains (or bodies) start at the same time from points A and B towards each other and after crossing they take a and b sec in reaching B and A respectively, then: (A's speed) : (B's speed) = (b : a)

Therefore, Ratio of the speeds of two trains = = 3 : 2

A) 68 kmph | B) 52 kmph |

C) 76 kmph | D) 50 kmph |

Explanation:

Let the speed of the faster train be 'X' kmph,

Then their relative speed= X - 48 kmph

To cross slower train by faster train,

Distance need to be cover = (400 + 600)m = 1 km. and

Time required = 180 sec = 180/3600 hr = 1/20 hr.

Time = Distance/Speed

=> 1/20 = 1/(x-48)

X = 68 kmph

A) 10 sec | B) 48 sec |

C) 36 sec | D) 56 sec |

Explanation:

Given speed of jogger = 9 kmph

Speed of train = 45 kmph

As they are in same direction,

Relative speed = 45 - 9 = 36 kmph = 36x5/18 = 10 m/s

Distance = 240 + 120 = 360 mts

Time = distance/speed = 360/10 = 36 sec.

A) 1 : 2 | B) 3 : 1 |

C) 4 : 7 | D) 3 : 2 |

Explanation:

Let the speeds of the two trains be x m/sec and y m/sec respectively.

Then, length of the first train = 27 x meters, and

length of the second train = 17 y meters.

(27 x + 17 y) / (x + y) = 23

=> 27 x + 17 y = 23 x + 23 y

=> 4 x = 6 y

=> x/y = 3/2.

A) 29 sec | B) 58 sec |

C) 36 sec | D) 44 sec |

Explanation:

Speed of train relative to man = 67 - 7 = 60 km/hr.

= 60 x 5/18 = 50/3 m/sec.

Time taken to pass the man = 600 x 3/50 = 36 sec.

A) 1 : 3 | B) 2 : 1 |

C) 3 : 1 | D) 1 : 2 |

Explanation:

Given that train K crosses a pole in 30 seconds and train L crosses the same pole in one minute and 15 seconds.

Let the length of train K be Lk and that of train L be Ll

given that Lk = 3/4 Ll

As the train K and L crosses the pole in 30 seconds and 80 seconds respectively,

=> Speed of train K = sk = Lk/30

Speed of train L = sl = Ll/80

Lk = 3/4 Ll

=> sk = 3/4 Ll/(30) = Ll/40

Ratio of their speeds = sk : sl

= Ll/40 : Ll/80

=> 1/40 : 1/80 = 2 : 1