question_answer

The circum-radius of an equilateral triangle is 8 cm. The in-radius of the triangle is

A) 3.25 cm            

B) 3.50 cm

C) 4 cm                

D) 4.25 cm

Correct Answer: C

Solution :

\[\because \]       \[\frac{OC}{OD\,}=\frac{2}{1}\] \[\Rightarrow \]   \[\frac{8}{OD}=\frac{2}{1}\] \[\Rightarrow \]   \[OD=4\,cm\]             In radius = 4 cm