Q10. 504 cones, each of diameter 3.5 cm and height 3 cm, are incited and recast into a metallic sphere. Find the diameter of the sphere and hence find its surface area.

Q9. A wooden toy rocket is in the shape of a cone mounted on a cylinder. The height of the entire rocket is 26 cm, while the height of the conical part is 6 cm. The base of the conical portion has a diameter of 5 cm, while the base diameter of the cylindrical portion is 3 cm . If the conical portion is to be painted orange and the cylindrical portion yellow, find the area of the rocket painted with each of these colours. [π = 3.14]

Q8. Rahul ,an engineering student ,prepared a model shaped like a cylinder with two cones attached at its two ends. The diameter of the model is 3 cm and its length is 12 cm. If each conical part has height of 2 cm. find the cost of painting the outer surface of the model at R. 12.50 per cm²(assume the outer and inner dimensions of the model to be nearly the same )

Q7. A solid is composed of a cylinder with hemispherical ends. If the whole length of the solid is 104 cm and the radius of each of its hemispherical ends is 7cm,Find the cost of polishing its surface at the rate of Rs.10 per dm².

Q6. A solid is in the shape of a cone mounted on a hemisphere of same base radius. If the curved surface areas of the hemispherical part and the conical part are equal then find the ratio of the radius and the height of the conical part.

Q5. A solid wooden toy is in the form of hemisphere surmounted by a cone of same radius .The radius of the hemisphere is 3.5cm and the total wood used in the making of toy is 166 5/6cm³. Find the cost of painting the hemispherical part of the toy at the rate of Its. 10 per cm².

Q4. Due to some floods some welfare associations jointly requested the government to get 100 tents fixed immediately and offered to contribute 50% of the cost. If the lower part of each tent is of the form of a cylinder of a diameter 4.2 m and height 4m with the conical upper part of some diameter but of height 2.8 m ,and the canvas to be used costs R. 100 per square meter ,Find the amount the associations will have to pay. What values are shown by these associations?

Q3. A vessel is in the form of a hemispherical bowl mounted by a hollow cylinder. The diameter of the hemisphere is 14 cm and the total height of the vessel is 13 cm. Find the inner surface area of the vessel.

Q2. A sphere and a cube have equal surface areas. Show that the ratio of the volume of sphere to that of the cube is √6 : √π

Q1. Three cubes each of volume 216 cm3 are joined end to end to form a cuboid .Find the total surface area of the resulting cuboid.