Management Aptitude Test 2017 Paper

(c) 514.28 $\mathit{c}{\mathit{m}}^2$

Edge of the cube = 20 cm (given)
∴ Diameter of the circle = Edge of the Cube = 20 cm
So, radius of the circle (r) = 10 cm
Now, Area of the cube = 6 ${\mathit{a}}^2$
= 6 x 20 x 20 = 2400 $\mathit{c}{\mathit{m}}^2$
Area of one circle = $\mathit{\pi }{\mathit{r}}^2=\frac{22}{7}$ x 10 x 10 $\mathit{c}{\mathit{m}}^2$
= 314.28 $\mathit{c}{\mathit{m}}^2$
Area of 6 circles = 6 x $\mathit{\pi }{\mathit{r}}^2$
= 6 x 314.28 $\mathit{c}{\mathit{m}}^2$ = 1885.71 $\mathit{c}{\mathit{m}}^2$
∴ Total unpainted surface of the cube
= (2400 - 1885.71) $\mathit{c}{\mathit{m}}^2$
= 514.28 $\mathit{c}{\mathit{m}}^2$