Question

Area of a circle is 616 square cm. The circle is surrounded by a path 2 meter wide. What is the area of this path?

Answer 1

Area of path = 616 sq. cm

Let radius of circle is r cm

Area of circle = 616 sq. cm

⇒ πr²= 616

⇒ 22/7 x r² = 616

⇒ r² = (616 x 7)/22

⇒ r² = 28 x 7

⇒ r² = 196

⇒ r = 14 cm

After 2 cm wide road let the radius is

R = r + 2

R = 14 + 2 = 16 cm

Area of path = = πR² – πr²

= π(R² – r²) 

= 22/7 x (16² – 14²)

= 22/7 x (256 – 196) 

= 22/7 x 60

= 188.57 sq. cm.