Question

A hollow sphere in which a circus motorcyclist performs his stunts, has an inner diameter of $7m$. Find the area available to the motorcyclist for riding. (Take $\pi =\frac{22}{7}$)

Answer 1

Inner diameter of the hollow sphere, $2r=7m$
Available area to the motorcyclist for riding $=$ Inner surface area of the sphere
$=4\pi r^2=\pi {\left(2r\right)}^2$
$=\frac{22}{7}\times 7^2$
Available area to the motorcyclist for riding $=154sq.m$