Question

What is the area of the semicircle with diameter 20cm

Answer 1

Step-by-step explanation:

Heya,  

Diameter = 20cm

Radius = 20/2 cm = 10cm  

We know,

Circumference of Semi-circle = r(π + 2)  

∴ Circumference of Semi-Circle  

= 10(22/7 + 2) cm

= 10(22 + 14/7) cm

= 10(36/7)cm

= 360/7 cm  

Hope it helps !

Answer 2

As we know that area of a semicircle is

$\pi {r}^{2} \div 2$

Given diameter is 20cm

Radius(r) =d/2

=20/2

=10cm

Area of semicircle=(22/7*10^2)/2

=3.14*100/2

=314/2

=157cm