Question

The area of the square is 100 square centimeters. What is the area of the circle?

Answer 1

$length \: of \: 1 \: side = diameter$

$area \: = {l}^{2} \\ 100 = {l}^{2} \\ \sqrt{100} = l \\ l = 10$

$diameter = 2 \times radius \\ 10 = 2 \times radius \\ radius = 5$

$circle \: area = pi \times {r}^{2} \\ circle \: area = 3.142 \times {5}^{2} \\ circle \: area = 3.142 \times 25 \\ circle \: area = 78.55 {cm}^{2}$

Answer 2

Area of the circle: 78.55 centimeters