Madhya Pradesh Police Exam Model Paper 7

Given:
Circumference of circle = 176 cm
Concepts used:
Circumference of circle = 2 × π × radius of the circle
The diameter of circle = 2 × radius of the circle
Calculation:
Let the radius of the circle be r cm.
Circumference of circle = 2 × π × radius of circle
$\Rightarrow 176\mathit{c}\mathit{m}=2\times \mathit{\pi }\times \mathit{r}$
$\Rightarrow 176\mathit{c}\mathit{m}=2\times 22/7\times \mathit{r}$
$\Rightarrow 176\mathit{c}\mathit{m}=44/7\times \mathit{r}$
$\Rightarrow \left(176\times 7\right)/44=\mathit{r}$
⇒ r = 28 cm
Diameter of circle = 2 × r
$\Rightarrow 2\times 28\mathit{c}\mathit{m}$
$\Rightarrow 56\mathit{c}\mathit{m}$ .
∴ The diameter of the circle is 56 cm.