question_answer

The given figure shows an isosceles triangle and a semicircle with centre O.

If the radius of the semicircle is 2.8 cm. What is the perimeter of the figure?

A)  15.6 cm           

B)  18.8 cm 

C)  16.8 cm           

D)  20.4 cm

Correct Answer: B

Solution :

(b): Circumferences of circle \[=2\pi r\] \[=2\times \frac{22}{7}\times 2.8=17.6\,\,cm\] Circumferences of semicircle \[=8.8\text{ }cm\] Perimeter of the figure \[=(5+5+8.8)=18.8cm\]