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  1. 2 + 22 + 23 + ... + 29 = ?

  2. A.

    2044

    B.

    1022

    C.

    1056

    D.

    None of these

    View Answer

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    Answer : Option B

    Explanation :

    This is a G.P. in which a = 2, r= \(\frac {2^2 } { 2 } \)= 2 and n = 9.

    Sn =\( a (\frac {( r^n-1) } { (r-1) } )\)=\(2*\frac {( 2^9-1) } {(2-1) }\)= 2 x (512 - 1)   = 2 x 511   = 1022.

           
       


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