Home
Class 11
MATHS
If the sums of n terms of two A.P.s are ...

If the sums of `n` terms of two A.P.s are in ratio `(3n+2):(2n+3)` , find the ratio of their 12th terms.

Text Solution

Verified by Experts

According to question
`(n/2[2a1​+(n′−1)d1​] )/(n/2[2a2​+(n′−1)d2​])​=(2n+3​)/(3n+2)`
Put n′=10 for the ratio of 10th terms
`⇒(a1​+9d1​​ )/(a2​+9d2​)=(2×19+3​)/(3×19+2)`
[putting`2n−1​=9=>n=19]` ...
Promotional Banner

Topper's Solved these Questions

  • BINOMIAL THEOREM

    RD SHARMA|Exercise Solved Examples And Exercises|228 Videos

Similar Questions

Explore conceptually related problems

If the sums of n terms of two Aps are in the ratio ( 2n+3) :(3n+2) , find the ratio of their 10th terms.

The sums of n terms of two AP's are in the ratio (3n-13):(5n+21). Find the ratio of their 24th terms.

The sums of first n terms of two A.P.'s are in hte ratio (7n+2):(n+4). Find the ratio of their 5th terms.

If the sum of first n terms of two A.P.'s are in the ratio 3n+8 : 7n+15, then the ratio of 12th term is

The ratio between the sum of first n terms of two A.P.'s are in the ratio (7n-5) : (5n+17). Find the ratio of their 10th terms.

The ratio of the sum of n terms of two A.P.'s is (7n-1):(3n+11), find the ratio of their 10th terms.

The ratio of sums of n terms of two A.P'. is (7n + 1) : (4n + 27). Find the ratio of their 11th terms.

RD SHARMA-ARITHMETIC PROGRESSIONS-Solved Examples And Exercises
  1. Write the value of n for which nth terms of the A.P.s 3,10,17. And 63,...

    Text Solution

    |

  2. if m t h term of an A.P. is n\ a n d\ n t h term is m , then write its...

    Text Solution

    |

  3. If the sums of n terms of two A.P.s are in ratio (3n+2):(2n+3) , find ...

    Text Solution

    |

  4. If 7th and 13th terms of an A.P. be 34 and 64 respectively, then its...

    Text Solution

    |

  5. If the sum of p terms of an A.P. is q and the sum of q terms is p, the...

    Text Solution

    |

  6. If the sum of n terms of an A.P. be 3n^2-n and its common difference i...

    Text Solution

    |

  7. Sum of all two digit numbers which when divided by 4 yield unity as re...

    Text Solution

    |

  8. There are n A.M.s between 3 and 17. The ratio of the last mean to the ...

    Text Solution

    |

  9. If Sn denotes the sum of first n terms of an A.P. <an> such that (Sm)/...

    Text Solution

    |

  10. The first and last terms of an A.P. are 1 and 11. If the sum of its ...

    Text Solution

    |

  11. If the sum of m terms of an A.P., is 3m^2+5m then which of its terms i...

    Text Solution

    |

  12. If the sum of n terms of an A.P. is 2n^2+5n ,\ then its nth term is ...

    Text Solution

    |

  13. If a1,a2,a3, ,an are in A.P. with common difference d(where d!=0) , ...

    Text Solution

    |

  14. If the arithmetic progression whose common difference is nonzero the ...

    Text Solution

    |

  15. Find the four numbers in A.P., whose sum is 50 and in which the greate...

    Text Solution

    |

  16. If n arithmetic means are inserted between 1 and 31 such that the rati...

    Text Solution

    |

  17. Let Sn denote the sum of n terms of an AP whose first term is a. If co...

    Text Solution

    |

  18. The first and last term of an A.P. are a and l respectively. If S is...

    Text Solution

    |

  19. If the sum of first n even natural numbers is equal to k times the sum...

    Text Solution

    |

  20. If the first second and last term of an A.P. are a ,\ b ,\ a n d\ 2a\ ...

    Text Solution

    |