fine the radius of a sphare with a surface area of 90 square meter

Question

The surface area of a sphare is given by formula S=4πr2. Fine the radius of a sphare with a surface area of 90 square meter. ( use 13.5 for π )

Answer 1

spheer area=90=4*pi*rad*rad

rad=sqrt(90/4/pi)

=sqrt(22.5/3.14159365...) or sqrt(22.5*0.3183098861827565)

=sqrt(7.161972439112022)

=2.676186174224809