Question

An umbrella has 8 ribs which are equally spaced. Assuming umbrella to be a flat circle of radius 45 cm, find the area in $c{m}^2$ of each rib of the umbrella. [2 MARKS]

Answer 1

Concept: 1 Mark
Application: 1 Mark

Radius = 45cm

8 ribs implies angle subtend between consecutive ribs
$=\frac{360}{8}={45}^{\circ }$

Area of each rib
$=\frac{45}{360}\times \pi \times {45}^2$

$=795.22c{m}^2$