COOL QQQ.

Area of square is side² So area of square PQRS is 400 cm² now area of circle is PIEr² so area of circle is 153.86 cm² area of grey part is 400-153.86 = 246.14 cm²

$\mbox{Area of the grey part = area of the square - area of the circle}$

$\mbox{Area of the grey part} = 20^2 - \pi (7^2)$

$\mbox{Area of the grey part} = 400 - 49 \pi$

$\mbox{Area of the grey part} \approx$ $\large \color{#D61F06}\boxed{246}$

Area of square = side² = 40 * 40

                          = 400 cm²

area of circle = PIEr² radius = 7 cm area of circle = (22 / 7) * 7 * 7 = 22 * 7

                      =  154 cm²

area of grey part = 400 - 154

                            =   246 cm²