Question

If the perimeter of a semicircle protractor is 36cm. Find its diameter ( Use π=22/7)

Answer 1

perimeter of semicircle= 2πr/2+diameter

=πr+2r

also, πr+2r=36

22/7 X r + 2r=36

r+2r=36 X 7/22

3r=18 X 7/11

r=18 X 7/11 X 1/3

r=6 X 7/11

r=42/11

r=3.81cm

therefore the diameter is 2 X 3.81

=7.62cm

Answer 2

Step-by-step explanation:

perimeter of circle = 2Πr

perimeter of semi circle = Πr

given...

Πr = 36

22/7r = 36

r = 36. × 7

--------

22

r = 126

---------

11

now d = 2r

= 2 × 126/11

= 252/7cm