Question

the radius of a sphere is 7 cm . find it's curved surface area
$(\pi = \frac{22}{7} )$

Answer 1

radius = 7 cm

c.s.a = 4 pie r2

= 4 * 22/7 * 7 * 7

= 88 * 7

=616 cm2

Answer 2

R=7 cm
$Csa = \: 2\pi {r}^{2}$


Therefore
$2\pi {r }^{2} \\ 2 \times 22 \div 7 \times {7}^{2} \\ 44 \times 77 \\ 308$
Ans =308 cm sq