question_answer

The diameter of a circular pond is 40 m. There is a path around this pond of width 5 m, the area of the path is

A) \[200\,\pi \,{{m}^{2}}\]                     

B) \[400\,\pi \,{{m}^{2}}\]

C) \[225\,\pi \,{{m}^{2}}\]           

D) \[425\,\pi \,{{m}^{2}}\]

Correct Answer: C

Solution :

    

According to the. question,

Area of path \[=\pi \,({{R}^{2}}+{{r}^{2}})=\pi \,({{25}^{2}}-{{20}^{2}})\]

\[=\pi \,(45)(5)=225\,\pi \,{{m}^{2}}\]