### Discussion :: Chain Rule - General Questions (Q.No.9)

Prakash said: (Oct 17, 2010) | |

Please explain another method for this problem. |

Avaneet said: (Aug 10, 2011) | |

What is cogs? |

Rahul said: (Oct 7, 2011) | |

Cogs = Tooth on the rim of gear wheel... If cogs increases , wheel circumference increases then revolution decreases dats means 6 cogs,less circumference,more revolution.. 14 cogs, more circumference ,less revolution compared to 6 cogs wheel cogs is inversely proportional to revolutions 6 cogs gives 21 revolution 1 cog will give =6*21 revolutions. 14 cog will give = 6*21/14=9 |

Pankaj Kanaujiya said: (Jun 20, 2012) | |

Lets firstly we take small cog..... 6 cog = 21 revolution 1 cog = 21*6 = 126 revolution now we have to find the revolution of 14 cog then 14 cog = 126/14 =63/7 = 9 hence answer is B. have a good day!!! |

Prasanna said: (Nov 3, 2015) | |

Hi guys, If you think in another way it would be easy. Larger wheel has 14 cogs. Smaller has 6 cogs. So for one revolution of smaller wheel bigger will rotate 6/14. 1 revolution-----6/14. 21 revolution----21*6/14. And is 9. |

Anonymous said: (May 7, 2016) | |

@Rahul. How is cogs inversely proportional to revolutions? |

Soundarya said: (Aug 21, 2016) | |

@Anonymous. Because the given cogs are 6 which is less than that of the revolutions 2, which is more. |

Karthik said: (Jun 17, 2017) | |

21 is of small cog then why is it compared with lager ration? |

Sandeep said: (Sep 14, 2017) | |

You can say 6 persons can do a piece of work in 21 days than in how many days 14 person can do the same work. 6*21 =14*x. =9. |

Sandeep said: (Sep 14, 2017) | |

You can say 6 persons can do a piece of work in 21 days then in how many days 14 person can do the same work. 6*21 =14*x. =9. |

Vinay Vishwakarma said: (Feb 13, 2019) | |

Which formula use for this question? please explain anyone. |

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