SSC CGL 16 Aug 2015 Shift 1 Paper

Here, $3^2+4^2$ = $5^2$
It is a right angled triangle.

Riadius of circum – circle ${\mathit{C}}_2$ = $\frac{5}{2}$ cm. because
AC = Diameter of circle
Semi-perimeter of ΔABC(s)
= $\frac{3+4+5}{2}$ = 6 cm
Area of ΔABC = $\frac{1}{2}$ × 3 × 4
= 6 sq. cm.
∴ In-radius = $\frac{\mathit{\Delta }}{\mathit{s}}$ = $\frac{6}{6}$ = 1 cm
∴ $\frac{\mathrm{Area}\mathrm{of}{\mathit{C}}_1}{\mathrm{Area}\mathrm{of}{\mathit{C}}_2}$ = $\frac{\mathit{\pi }\times 1^2}{\mathit{\pi }\times {\left(\frac{5}{2}\right)}^2}$
= $\frac{1}{\frac{25}{4}}$ = $\frac{4}{25}$