Two circles touch internally. The sum of their areas is 116π sq. cm and the distance between their centres is 6 cm. The radii of the circles are respectively

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?

If the difference between the circumference and radius of a circle is 37 cm, then the area of the circle is

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

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

X, Y and Z are three equilateral triangles. The sum of the areas of X and Y is equal to the area of Z. If the side lengths of X and Y are 6 cm and 8 cm respectively, then what is the side length of Z?