Saw the largest circle on a square board with a side length of 20 cm. The area of the circle is______ Square centimeter. What's the rest of the leftover material______ Square centimeter

Saw the largest circle on a square board with a side length of 20 cm. The area of the circle is______ Square centimeter. What's the rest of the leftover material______ Square centimeter

3.14 × (20 △ 2) 2 = 3.14 × 10 × 10 = 314 (bisecting centimeter); 20 × 20-314, = 400-314, = 86 (bisecting centimeter); answer: the area of this circle is 314 square centimeter, and the remaining leftover material is 86 square centimeter