Find the perimeter of a semicircular protractor whose diameter is 14 cm.
Question:

Find the perimeter of a semicircular protractor whose diameter is 14 cm.

Solution:

Perimeter of a semicircular protractor = Circumference of semicircular protractor + diameter of semicircular protractor

$=\frac{1}{2}(2 \pi r)+d$

$=\pi r+d$

$=\pi \frac{d}{2}+d$

$=\frac{22}{7} \times 7+14$

$=22+14$

$=36 \mathrm{~cm}$

Hence, the perimeter of a semicircular protractor is 36 cm.