Each side of a given polygon is parallel to either the X or the Y axis. A corner of such a polygon is said to be convex if the internal angle is 90o or concave if the internal angle is 270o. If the number of convex corners in such a polygon is 25, the number of concave corners must be
Correct Answer : C
A square piece of cardboard of sides ten inches is taken and four equal square pieces are removed at the corners. The sides are then turned up to form an open box. Then the maximum volume such a box can have is
A circle is inscribed in a given square and another circle is circumscribed about the square. What is the ratio of the area of the inscribed circle to that of the circumscribed circle ?
How many bricks each measuring 50 cm x 20 cm x 12 cm will be needed to construct a wall be needed to construct a wall 16m long, 12m high and 45 cm thick ?