Find the cost of sinking a tubewell 280 m deep, having diameter 3 m at the rate of Rs. 3.60 per cubic metre. Find also the cost of cementing its inner curved surface at Rs. 2.50 per square metre.

Ravish wanted to make a temporary shelter for his car by making a box-like structure with tarpaulin that covers all the four sides and the top of the car (with the front face as a flap which can be rolled up). Assuming that the stitching margins are very small, and therefore negligible, how much tarpaulin would be required to make the shelter of height 2.5 m with base dimensions 4 m × 3 m?

If the radius of a cylinder is doubled and the height remains same, the volume will be

If each edge of a cube, of volume V, is doubled, then the volume of the new cube is

The height h of a cylinder equals the circu,ference of the cylinder. In terms of h, what is the volume of the cylinder?

Find the lateral surface area and the total surface area of a cube of side 8 cm.

The length and breadth of a hall are in the ratio 4 : 3 and its height is 5.5 metres. The cost of decorating its walls (including doors and windows) at Rs. 6.60 per square metre is Rs. 5082. Find the length and breadth of the room.

The dimensions of a rectangular box are in the ratio of 2 : 3 : 4 and the difference between the cost of covering it with sheet of paper at the rates of Rs. 8 and Rs. 9.50 per m² is Rs. 1248. Find the dimensions of the box.

A culindrical water tank of diameter 1.4 m and height 2.1 m is being fed by a pipe of diameter 3.5 cm through which water flows at the rate of 2 metre per second. In how much time the tank will be filled?

If each edge of a cuboid of surface area S is doubled, then surface area of the new cuboid is

If the height of a cylinder is doubled, by what number must the radius of the base be multiplied so that the resulting cylinder has the same volumes as the original cylinder?