Aptitude Discussion

Q. |
Two identical trains $A$ and $B$ running in opposite direction at same speed tale 2 min to cross each other completely. The number of bogies of $A$ are increased from 12 to 16. How much more time would they now require to cross each other? |

✖ A. |
40 sec |

✖ B. |
50 sec |

✖ C. |
60 sec |

✔ D. |
20 sec |

**Solution:**

Option(**D**) is correct

Total initial bogies is $12+12 = 24$

Additional bogies $= 16−12 = 4$

24 bogies take 2 minutes.

4 bogies will take:

\(=\dfrac{2\times 60}{24}\times 4\)

= **20 sec.**

**Chirag Goyal**

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**Ash**

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How did we get 60? In the solution??s

**Anita**

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total boggies 24 take 2 min i.e; 120 sec

1 boggie will take 5 sec

therefore 4 boggies will take 5 * 4=20 sec

4 bogies increase in one train is similar to 2 bogies increase in 2 trains each.

so 12 bogies takes 2 mins and 2 bogies will take 1/6 of 2 mins

i.e. 20 sec more.