The first term of a G.P. is 7, the last term | vedclass

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Question

(d) $a = 7\,\,{\rm{and}}\,\,a{r^{n - 1}} = 448$

Now,${S_n} = \frac{{a({r^n} - 1)}}{{r - 1}} = 889$

$ \Rightarrow \frac{{(a{r^{n - 1}}.r - a)}}{{

Vedclass · Accepted Answer

$2$

Vedclass · Answer

(d) $a = 7\,\,{\rm{and}}\,\,a{r^{n - 1}} = 448$

Now,${S_n} = \frac{{a({r^n} - 1)}}{{r - 1}} = 889$

$ \Rightarrow \frac{{(a{r^{n - 1}}.r - a)}}{{r - 1}} = 889$

==> $\frac{{448r - 7}}{{r - 1}} = 889$

==> $r = 2$.

The first term of a $G.P.$ is $7$, the last term is $448$ and sum of all terms is $889$, then the common ratio is

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