Question

If point C is the center of the bigger circle and it also lies on the circumference of the smaller circle, then find the ratio of the green area to the yellow area

• A. 1:2
• B. 3:4
• C. 1:3
• D. 2:3

Answer 1

The correct option is C 1:3

Let the radius of the smaller circle be r

Radius of the bigger circle = diameter of the smaller circle

So, Radius of the bigger circle = 2r

Green area =$\pi r^2$

Yellow area = Area of the bigger circle - Area of the smaller circle
Yellow area $=\pi (2r{)}^2-\pi r^2=4\pi r^2-\pi r^2=3\pi r^2$

Ratio of green area to yellow area is
$\pi r^2:3\pi r^2=1:3$