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If V is the volume of a cuboid of dimens...

If V is the volume of a cuboid of dimensions a,b,c and S is its surface area, then prove that
`1/V=2/S(1/a+1/b+1/c)`

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MODERN PUBLICATION-SURFACE AREAS AND VOLUMES-EXERCISE
  1. The length and breadth of a room are in the ratio 4:3 and its height i...

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  2. A class room is 7 m long, 6.5 m wide and 4 m high. It has one door 3 m...

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  3. If V is the volume of a cuboid of dimensions a,b,c and S is its surfac...

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  4. The areas of three adjacent faces of a cuboid are x,y and z. if the vo...

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  5. Find the volume of the cuboid whose dimensions are length=26m, breadth...

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  6. Find the volume of the cuboid whose dimensions are length=24 m, breadt...

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  7. If the areas of three adjacent faces of a cuboid are 8cm^2,18cm^2 and ...

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  8. The breadth of a room is twice its height and is half of its length. T...

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  9. Two cubes, each of volume 512cm^3 are joined end to end. Find the surf...

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  10. How many planks of dimensions (5mxx25cmxx10cm) can be stored in a pit ...

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  11. How many bricks will be required to construct a wall 12 m three smalle...

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  12. Given that 1 cubic cm of marble weights 0.25 kg, the weight of marble ...

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  13. A river 3 m deep and 40 m wide is flowing at the rate of 2 km per hour...

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  14. How many persons can be accommondatd in a dining hall of dimensions (2...

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  15. The volumes of a cuboid is 1536cm^2. Its length is 16 m and its breadt...

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  16. In a shower, 5 cm of rain falls, find the volume of water that falls o...

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  17. A rectangular container, whose base is a square of side 5 cm, stands o...

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  18. A field is in the form of a rectangle of length 18 m and width 15 m. A...

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  19. A rectangular tank is 80 m long and 25 m braod water flows into it thr...

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  20. Find the curved surface area of a right circular cylinder at height 21...

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