Banking Quantitative Aptitude Sample Paper Quantitative Aptitude Sample Paper-31

  • question_answer
    The value of \[\frac{{{(8.1)}^{3.6}}\times {{(9)}^{2.7}}}{{{(81)}^{4.2}}\times (3)}\]is [SSC (CGL) 2012]

    A) 3                                 

    B) 6      

    C) 9         

    D) 8.2

    Correct Answer: C

    Solution :

    \[\frac{{{(81)}^{3.6}}\times {{(9)}^{2.7}}}{{{(81)}^{4.2}}\times 3}=\frac{{{({{3}^{4}})}^{3.6}}\times {{({{3}^{2}})}^{2.7}}}{{{({{3}^{4}})}^{4.2}}\times 3}\]
    \[=\frac{{{3}^{14.4}}\times {{3}^{5.4}}}{{{3}^{16.6}}\times {{3}^{1}}}={{3}^{14.4\,\,+\,\,5.4\,\,-\,\,16.8-1}}\]
    \[\left[ \begin{align}   & \because {{a}^{m}}\times {{a}^{n}}={{(a)}^{m+n}} \\  & {{a}^{m}}\div {{a}^{n}}={{(a)}^{m-n}} \\ \end{align} \right]\]
    \[={{3}^{19.8-17.8}}={{3}^{2}}=9\]


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