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Practice Time 10E

1. Find the volume of the following solids formed by the unit cubic blocks.
(a) (b) (c)

2. Find the volume of the following.
(a) A cuboid of dimensions 15 cm × 8 cm × 12 cm

(b) A cuboid of dimensions 3 m × 2 m × 1.5 m
(c) A cube of side 8 cm

(d) A cube of side 1.3 m

(e) A cylinder of base radius 14 cm and height 28 cm
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(f) A cylinder of base radius 0.35 m and height 140 cm (write answer in m )
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3. A box has a volume of 13,400 cm and the base area of 670 cm . What is the height of the box?
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4. The dimensions of a water tank are 4.2 m, 3 m and 1.8 m. What will be its capacity in litres?
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5. How many cubes, each of side 0.5 cm, are required to make a cube of volume 8 cm ?
6. A metallic sheet in the form of a cuboid is 27 cm long, 4 cm broad, and 2 cm thick. It is melted into
a cube. What will be the side of the cube?

7. How many cubic metres of earth must be dug to construct a well 14 m deep and of diameter 2.8 m?

8. If the length of each edge of a cube is tripled, what will be the change in its volume?
9. A cube of side 6 cm is cut into 1 cm cubes. Find the ratio of the surface areas of the original cube
and cut-out cubes.

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10. The radius and height of a cylinder are in the ratio 3 : 2, and its volume is 19,404 cm . Find its radius
and height.
11. The radius of a cylinder is r and its height is h. Find the change in the volume if the height is doubled.

12. The ratio of the radii of two cylinders is 1 : 2, and the ratio of their heights is 2 : 3. What will be the
ratio of their volumes?

13. A cylindrical container with a base radius of 1.4 cm and a height of 77 cm is full of water. Find the
capacity of the container in litres.
14. Water is poured into a cuboidal reservoir at the rate of 60 litres per minute. If the volume of the
reservoir is 108 m , find the number of hours it will take to fill the reservoir.
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Brain Sizzlers
A cube fits exactly into a cylinder of height 10 cm. What will be the volume and surface area of
the cube?

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