Question Text
Question 1 :
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 2 :
The radius of a spherical balloon increases from 7 cm to 14 cm as air is being pumped into it. Find the ratio of surface areas of the balloon in the two cases.
Question 3 :
A small village, having a population of 5000, requires 75 litres of water per head per day. The village has got an overhead tank of measurement 40 m × 25 m × 15 m. For how many days will the water of this tank last?
Question 4 :
The diameter of a sphere is decreased by $25\%$. By what per cent does its curved surface area decrease?
Question 5 :
State true or false: Sphere whose radius = r, the surface area must be $4\pi r^{2}$.
Question 6 :
Find the volume of a sphere whose surface area is 154 $cm^2$ .
Question 7 :
What length of tarpaulin 3 m wide will be required to make conical tent of height 8 m and base radius 6 m? Assume that the extra length of material that will be required for stitching margins and wastage in cutting is approximately 20 cm (Use $\pi$= 3.14).
Question 8 :
The paint in a certain container is sufficient to paint an area equal to 9.375 $m^2$ . How many bricks of dimensions $22.5cm\times10cm\times7.5cm$ can be painted out of this container?
Question 9 :
A solid cube of side 12 cm is cut into eight cubes of equal volume.Find the ratio between their surface areas.
Question 10 :
Figures that can be drawn easily on our notebooks or cardboards are called ________