Question 1 :
The inner diameter of a circular well is 3.5 m. It is 10 m deep. Find the cost of plastering this curved surface at the rate of Rs 40 per $m^2$.Assume $\pi$ =$\frac{22}{7}$

Question 2 :
The slant height and base diameter of a conical tomb are 25 m and 14 m respectively. Find the cost of white-washing its curved surface at the rate of Rs 210 per 100 $m^2$.

Question 3 :
<img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d23af59b460d7261f56c.jpeg' /> In the above image, a metal pipe is 77 cm long. The inner diameter of a cross section is 4 cm, the outer diameter being 4.4 cm. Find its inner curved surface area.Assume $\pi$ =$\frac{22}{7}$.

Question 4 :
State true or false: A cylinder and a right circular cone are having the same base and same height. The volume of the cylinder is three times the volume of the cone.

Question 5 :
<img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d240f59b460d7261f575.jpeg' /> In the above image, a wooden bookshelf has external dimensions as follows: Height = 110 cm, Depth = 25 cm, Breadth = 85 cm. The thickness of the plank is 5 cm everywhere. The external faces are to be polished and the inner faces are to be painted. If the rate of polishing is 20 paise per $cm^2$ and the rate of painting is 10 paise per $cm^2$ , find the total expenses required for polishing and painting the surface of the bookshelf.

Question 6 :
How many square metres of canvas is required for a conical tent whose height is 3.5 m and the radius of the base is 12 m?

Question 7 :
The height of a cone is 16 cm and its base radius is 12 cm. Find the curved surface area of the cone (Use $\pi$ = 3.14).

Question 8 :
The diameter of a roller is 84 cm and its length is 120 cm. It takes 500 complete revolutions to move once over to level a playground. Find the area of the playground in $m^2$ .Assume $\pi$ =$\frac{22}{7}$.

Question 9 :
Find the surface area of a sphere of diameter 3.5 m.

Question 10 :
A soft drink is available in two packs – (i) a tin can with a rectangular base of length 5 cm and width 4 cm, having a height of 15 cm and (ii) a plastic cylinder with circular base of diameter 7 cm and height 10 cm. Which container has greater capacity and by how much?

Question 11 :
State true or false. An edge of a cube measures r cm. If the largest possible right circular cone is cut out of this cube, then the volume of the cone (in $cm^3$) is $(\frac{1}{6})\pi r^3$.

Question 12 :
State true or false: Total surface area of hemisphere is $4\pi r^{2}$.

Question 13 :
It costs Rs 2200 to paint the inner curved surface of a cylindrical vessel 10 m deep. If the cost of painting is at the rate of Rs 20 per $m^2$ , find the capacity of the vessel.

Question 14 :
The radius of a sphere is 2r, then its volume will be

Question 15 :
State true or false: A cone, a hemisphere and a cylinder stand on equal bases and have the same height. The ratio of their volumes is 1 : 2 : 3.

Question 16 :
Find the surface area of a sphere of diameter 21 cm.

Question 17 :
Find the surface area of a sphere of radius 14 cm.

Question 18 :
The total surface area of a cube is 96 $cm^2$. Find the volume of the cube.

Question 19 :
The hollow sphere, in which the circus motorcyclist performs his stunts, has a diameter of 7 m. Find the area available to the motorcyclist for riding.

Question 20 :
A lead pencil consists of a cylinder of wood with a solid cylinder of graphite filled in the interior. The diameter of the pencil is 7 mm and the diameter of the graphite is 1 mm. If the length of the pencil is 14 cm, find the volume of the wood .

Question 21 :
The diameter of a sphere is decreased by $25\%$. By what per cent does its curved surface area decrease?

Question 22 :
Find the total surface area of a hemisphere of radius 10 cm. (Use $\pi$ = 3.14)

Question 23 :
Find the volume of the right circular cone with radius 3.5 cm, height 12 cm.

Question 24 :
The volumes of the two spheres are in the ratio 64 : 27. Find the ratio of their surface areas.

Question 25 :
Find the total surface area of a cone whose radius is $\frac{r}{2}$ and slant height 2l.