Question

Find the perimeter and area of a semi - circle whose diameter is 18.2 cm

Answer 1

Perimeter of a semicircle = πr + 2r = 9.1(π+ 2) = 46.8 cms

Area of the semicircle =(1/2)πr^2 = (1/2) (22/7) (9.1)^2 = 130.13 sq cms.

Answer 2

area of semicircle = π r² /2  = 22/7  x 9.1²/2  = 130.13cm²

perimeter of semicircle = π r  + d = (3.14 x 9.1) + 18.2 = 46.77cm