Class 8, Maths, Chapter 11, Exercise 11.4 Solutions
Q.1. Given a cylindrical tank, in which situation will you find surface area and in which situation volume.
(a) To find how much it can hold.
(b) Number of cement bags required to plaster it.
(c) To find the number of smaller tanks that can be filled with water from it.
Ans:
(a) Volume
(b) Surface area
(c) Volume
Q.2. Diameter of cylinder A is 7 cm, and the height is 14 cm. Diameter of cylinder B is 14 cm and height is 7 cm. Without doing any calculations can you suggest whose volume is greater? Verify it by finding the volume of both the cylinders. Check whether the cylinder with greater volume also has greater surface area?
Q.3. Find the height of a cuboid whose base area is 180 cm2 and volume is 900 cm3?
Q.4. A cuboid is of dimensions 60 cm × 54 cm × 30 cm. How many small cubes with side 6 cm can be placed in the given cuboid?
Q.5. Find the height of the cylinder whose volume is 1.54 m3 and diameter of the base is 140 cm?
Q.6. A milk tank is in the form of cylinder whose radius is 1.5 m and length are 7 m. Find the quantity of milk in litres that can be stored in the tank?
Q.7. If each edge of a cube is doubled,
(i) how many times will its surface area increase?
(ii) how many times will its volume increase?
Q.8. Water is pouring into a cuboidal reservoir at the rate of 60 litres per minute. If the volume of reservoir is 108 m3, find the number of hours it will take to fill the reservoir.
