Question

If $a,b,c,d,e,f$ are in G.P., then $b\times f$ is equal to

• A. $b\times c$
• B. $a\times e$
• C. $f\times d$
• D. $e\times c$

Answer 1

The correct option is D $e\times c$

Let first term and common ratio are $a$ and $r$ respectively, then G.P will be
$a,ar,a{r}^2,a{r}^3,a{r}^4,a{r}^5$
$b\times f=ar\times a{r}^5=a^2{r}^6$
Which is equal to $e\times c=a{r}^4\times a{r}^2=a^2{r}^6$
Therefore, option 'D' is correct.