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A cone is 8.4 cm high and the radius of ...

A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. The radius of the sphere is

A

4.2 cm

B

2.1 cm

C

2.4 cm

D

1.6 cm

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MODERN PUBLICATION-SURFACE AREAS AND VOLUMES-EXERCISE
  1. The radius of a sphere is 2r. Then its volume will be

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  2. The total surface area of a cube is 96cm^2. The volume of the cube is

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  3. A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melt...

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  4. In a cylinder radius is doubled and height is halved, curved surface a...

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  5. The total surface area of a cone whose radius is r/2 and slant height ...

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  6. Base radius of two cylinder are in the ratio 2 : 3 and their heights a...

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  7. The lateral surface area of a cube is 256cm^2. The volume of the cube ...

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  8. The number of planks of dimensions (4mxx50mxx20cm) that can be stored ...

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  9. The length of the longest pole that can be put in a room of dimensions...

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  10. The radius of a hemispheircal balloon increases from 6 cm to 2 cm is a...

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  11. The slant height of a right circular cone is 10 cm and its height is 8...

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  12. A cone and a hemispher have equal bases and equal volumes. Find the ra...

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  13. Three solid sphres of radius 1 cm, 6 cm and 8 cm, respectively are mel...

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  14. The ratio of the volumes of a right circular cylinder and a right circ...

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  15. If the ratio of the volumes of two spheres is 1:8, then the ratio of t...

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  16. If a solid sphere of radius r is melted and cast into the shape of a s...

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  17. A cone of semi vertical angle of alpha is inscribed in a sphere of rad...

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  18. How many cubical blocks wose edge measures 3 cm can be formed by melti...

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  19. How much length of the iron sheet 11 cm, wide is required for making a...

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  20. The slant side of a right circular cone is 10 m and its height 8 m. fi...

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