CDS | Elementary Mathematics | 3D Mensuration

A hollow spherical shell is made of a metal of density 7 g/cm³. If its internal and external radii are 3 cm and 6 cm respectively, then what is the mass of the shell? (take )

A hemispherical bowl of internal radius 18 cm contains a liquid. The liquid is filled in small cylindrical bottles of internal radius 3 cm and internal height 4 cm. What is the number of bottles used to empty the bowl?

A hospital room is to accommodate 56 patients. It should be done in such a way that every patient gets 2·2 m² of floor and 8·8 m³ of space. If the length of the room is 14 m, the breadth and the height of the room are respectively

A rectangular sheet is of length x and breadth y. If p is the volume of the cylinder formed by rolling the sheet along its breadth and q is the volume of the cylinder formed by rolling the sheet along its length, and q = 2p, the which one of the following is correct?

A tall cylinder container with circular based of radius 18 cm contains a good quantity of water. Metal balls each of radius 0.9 cm are immersed in it. How many balls are required to raise the water level by 3cm?