EPFO 2015 English Medium Solved Paper

Given, area of bigger circle
$=\frac{693}{2}{\mathrm{cm}}^2$
⇒ $\mathit{\pi }{\mathit{r}}_2^2$ $=\frac{693}{2}$
$\therefore {\mathit{r}}_2=10.5\mathit{c}\mathit{m}$
Perimeter (circumference) of bigger circle $=2\mathit{\pi }{\mathit{r}}_2$
$2\times \frac{22}{7}\times 10.5=66\mathit{c}\mathit{m}$
So, perimeter of smaller circle
$=66-22=44\mathit{c}\mathit{m}$
$\Rightarrow 2\mathit{\pi }{\mathit{r}}_1=44$
$\therefore {\mathit{r}}_1=7\mathit{c}\mathit{m}$
Hence, sum of the diameters of the twocircles
$=2{\mathit{r}}_1+2{\mathit{r}}_2=2\times 7\times +2\times 10.5$
$=14+21=35\mathit{c}\mathit{m}$