The ratio of the radius of two circles is 5:4. What is the ratio of their areas?

If the radii of circles A and B are in the ratio 1.5: 1, then the areas of the circles A and B will be in the ratio

If the radius of the circle is increased by 100%, then the area is increased by

The area of a circle is 40π² . The area of a square with sides equal to radius of the circle is

Two equal arcs of different circles C1 and C2 subtend angles of 60° and 75° respectively, at the centres. What is the ratio of the radius of C1 to the radius of C2?

The radius of a circle is 14 cm and the area of a sector is 102.7 sq. cm. The central angle of the sector is