The first and last terms of a $G.P.$ are $a$ and $l$ respectively; $r$ being its common ratio; then the number of terms in this $G.P.$ is

  • A

    $\frac{{\log l - \log a}}{{\log r}}$

  • B

    $1 - \frac{{\log l - \log a}}{{\log r}}$

  • C

    $\frac{{\log a - \log l}}{{\log r}}$

  • D

    $1 + \frac{{\log l - \log a}}{{\log r}}$

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