Diagonals of a Trapezium ABCD with AB‖CD intersect each other at the point O. If AB=2CD, then the ratio of the areas of ΔAOB and ΔCOD is

D, E, F are the mid - points of the sides BC, CA and AB respectively of a ΔABC. Then the ratio of the areas of DEF and ΔABC is D, E, F.

In a regular polygon, the exterior and interior angles are in the ration 1:4.The number of sides of the polygon is

The radius of the circumcircle of a right-angled triangle is 15 cm and the radius of its in circle is 6 cm. Find the sides of the triangle. 

The centroid of a ∆ABC is G. The area of ∆ABC is 60 cm². The area of ∆GBC is

A solid sphere of diameter 7 cm is cut into two equal halves. What will be the increase (in cm.²) in the total surface area?

If two complementary angles are in the ratio of 2:3. find the ratio of square of smaller angle to square of greater?

The diagonals AC and BD of a cyclic quadrilateral ABCD intersect each other at the point P. Then, it is always true that