Question

Work out area of this semi circle with diameter 10

Answer 1

Area of a circle is pi x r^2

R is the radius which is have the diameter: r = 10/2 = 5

Area of the full circle would be 3.14 x 5^2 = 3.14 x 25 = 78.5 square units.

A semi circle is half a full circle

Area of the semi circle = 78.5/2 = 39.25 square units.