Question

The exact area of a circle is 81 pi square inches what are the radius and diameter of the circle

Answer 1

area is pi*r^2

so if area is 81pi, means r=9

diameter is 2*pi*r =2*pi*9=18pi

Answer 2

To get the radius multiply 254.34 by 2 which is 508.68 and to get the radius you divide 254.34 by 2 and you get 127.17