In a circle, difference between the circumference and radius is 37 cm. Find the area (in cm²) of the circle?

What is the area ( in cm² ) of the circumcircle of a triangle whose sides are 6 cm , 8 cm and 10 cm respectively ? 

The radius of a cone is 20 cm and height is 21 cm, the total surface area of the cone is in square cm:

The curved surface area of cylindrical pillar is and its volume is . Find the ratio of its diameter to its height.

The diameter of a circle is equal to the perimeter of a square whose area is 3136 sq cm. What is the circumference of the circle?

If the height and the radius of the base of a cone are both doubled, the volume of the cone becomes _______ of its previous volume.