Well, since the area of the square is 27m^2, one side is 3*sqrt(3). The radius of the circle is half the length of a side, which here is (3/2)*sqrt(3). Now all you have to do is use the formula for the area of the circle, which is r^2*pi. Then,
(3/2)^2*(square(3))^2*pi =
= 2.25*3*3.14159 =
=21.2057325=
= 21.21
I hope it’s clear. 🙂