Selina Concise Class 8 Math Chapter 21 Surface Area Volume and Capacity Exercise 21D Solution
Concise Mathematics – Class 8 Selina Exercise 21D Solution by experts | 21D Selina Concise Solution Class 8 | Class 8 Selina Concise Ex 21D Page 242 Solution | RK Bansal Class 8 ICSE Book Solution Online.
(1) The height of a cfircular cylinder is 20 cm and the diameter of its base is 14 cm. Find:
(i) its volume (ii) its total surface area.
(2) Find the curved surface area and the total surface area of a right circular cylinder whose height is 15 cm and the diameter of the cross section is 14 cm.
(3) Find the height of the cylinder whose radius is 7 cm and the total surface are is 1100 cm square.
(4) The curved surface area of a cylinder of height 14 cm is 88 cm square. Find the diameter of the base of the cylinder.
(5) The ration between the curved surface area and the total area of a cylinder is 1:2. Find the ration between the height and the radius of the cylinder.
(6) Find the capacity of a cylindrical container with internal diameter 28 cm and height 20 cm.
(7) The total surface area of a cylinder is 6512 cm square and the circumfarence of its base is 88 cm. Find:
(i) its radius (ii) its volume
(8) The sum of the radius and the height of a cylinder is 37 cm and the total surface area of the cylinder is 1628 cm square. Find the height and the volume of the cylinder.
(9) A cylindrical pillar has radius 21 cm and height 4 m. Find:
(i) the curved surface area of the pillar
(ii) cost of polishing 36 such cylindrical pillars at the rate of Rs. 12 per meter square.
(10) If radii of two cylinders are in the ratio 4:3 and their hights are in the ratio 5:6, find the ratio of their curved surfaces.