Mensuration

Gap-fill exercise

  
Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
1. The diameter of a sphere is 6 cm. It is melted and drawn into a wire of diameter 2 mm. The length of the wire is m.
2. A solid sphere of radius r is melted and cast into the sphere of a solid cone of height r, the radius of the base of the cone is .
3. The material of a cone is converted into the shape of a cylinder of equal radius. If height of the cylinder is 5 cm, then height of the cone is cm.
4. The surface area of a sphere is 616 cm2. Its radius is cm.
5. A metallic hemisphere is melted and recast in the shape of a cone with the same base radius R as that of the hemisphere. If H is the height of the cone, then write the value of HR.
6. If the slant height of the frustum of a cone is 6 cm and the perimeters of the circular bases are 24 cm and 12 cm respectively. The volume of that frustum is cm2.
7. A solid piece of iron of dimensions 49 cm × 33 cm × 24 cm is moulded into a sphere. The radius of the sphere is cm.
8. A reservoir is in the shape of a frustum of a right circular cone. It is 8 m across at the top and 4 m across at the bottom. It it is 6 m deep, then its capacity is m3.
9. The curved surface area of a cylinder is 264 m2 and its volume is 924 m3. The ratio of its diameter to its height is : .
10. The diameters of the top and the bottom portions of a bucket are 42 cm and 28 cm respectively. If the height of the bucket is 24 cm, then the cost of painting its outer surface at the rate of 50 paise/cm2 is Rs .