Question

if the perimeter of semicircular protractor is 66 cm find the radius of the protector .π=3.14

Answer 1

C=2πr
C(semicircle)=or

66=3.14r
r=21.01cm

Answer 2

Answer:

21 cm

Step-by-step explanation:

Circumference of semicircle = $\pi r$

We are given that the perimeter of semicircular protractor is 66 cm

So, $\frac{22}{7} \times r =66$

$r = 66 \times \frac{7}{22}$

$r = 6 \times \frac{7}{2}$

$r = 3 \times \frac{7}{1}$

$r = 21$

Hence the radius of the protractor is 21 cm