What is the area of the shaded region. Radii of the circles are 7 cm and 14 cm respectively. Take .
Ratio of the circumferences of two circles is . What is the ratio of their areas?
Area of the shaded region is 66 . What is the area of the circle?
Circumference of the circle is equal to 88 cm. What is the ratio of area to its circumference? Take .
O is the centre of the circle. What is the area of the shaded region if radius of the circle is 18 cm. Take .