Question

if the perimeter of a protractor is 72 cm, calculate its area.

Answer 1

Hi ,

We know that shape of a protracter

is semicircle,

Let radius of the semicircle = r cm

Perimeter of the protracter = 72 cm

πr + 2r = 72

r ( π + 2 ) = 72

r ( 22/7 + 2 ) = 72

r ( 22 + 14 )/7 = 72

( 36/7 )r = 72

r = ( 72 × 7 )/36

r = 14 cm.

Therefore ,

Area of the protracter = area of the

but semicircle

= ( 22/7 ) (14)²/ 2

= ( 22 × 14 × 14 )/( 7 × 2 )

= 22 × 14

= 308 cm²

I hope this helps you.

:)

Answer 2

here is your ans.....