2. Solved Papers
  3. JEE Main & Advanced

JEE Main & Advanced JEE Main Paper (Held On 26 May 2012)

  • question_answer
    If the A.M. between \[{{\text{p}}^{\text{th}}}\]and \[{{\text{q}}^{\text{th}}}\]terms of an A.P. is equal to the A.M. between \[{{\text{r}}^{\text{th}}}\]and \[{{\text{s}}^{\text{th}}}\] terms of the same A.P., then p + q is equal to.   JEE Main Online Paper (Held On 26-May-2012)  

    A) r+s-1

    B) r+s-2

    C) r+s+1                    

    D) r+s

    Correct Answer: D

    Solution :

    Given:\[\frac{{{a}_{p}}+{{a}_{q}}}{2}=\frac{{{a}_{r}}+{{a}_{s}}}{2}\] \[\Rightarrow \]\[a+(p-1)d+a+(q-1)d\] \[=a+(r-1)d+a+(s-1)d\] \[\Rightarrow \]\[2a+(p+q)-2d=2a+(r+s)d-2d\] \[\Rightarrow \]\[(p+q)d=(r+s)d\Rightarrow p+q=r+s.\]


You need to login to perform this action.
You will be redirected in 3 sec spinner