Question
The area of the base of a right circular cone is 81π cm² and its height is 12
The area of the base of a right circular cone is 81π cm² and its height is 12
cm. What is the curved surface area (in cm2) of the cone?
The area of the base of a right circular cone is 81π cm πr2 = 81π ⇒ r2 = 81 ⇒ r = 9 The height of the cone is 12 cm The slant height of the cone (l) is AC = √ (92 + 122) ⇒ AC = 15 The curved surface area of the cone is π × 9 × 15 ⇒ 135π ∴ The curved surface area of the cone is 135π cm2More Mensuration Questions
- The volume and height of a cylinder are 2673 cm3 and 10.5 cm. Find the radius of the cylinder.
- A well of diameter 8 metres is dug 18 metres deep. Earth taken out of it was spread evenly all around it in the shape of a circular ring of width 2 metres ...
- On a rectangular wall of length 25 metres and height 20 metres, there is a window in the shape of triangle surmounted on a square. If the base of triangle ...
- The diameter of the base of a cylindrical drum is 70 cm and its height is 15 cm. The drum is full of water and the water from the drum is transferred to ‘n...
- A rectangular playground is fenced at Rs. 11/metre and the total cost is Rs. 1210. If the length to breadth ratio is 6:5, find the area of the playground.
- A cube has edge 13 m. Find its length of diagonal, surface area and volume.
- The length of a 540 metre long rope is 9 times the perimeter of a rectangular German park. Find the area of the rectangular park given that its length is 6...
- If the length of a rectangle is increased by 10% and its breadth is decreased by 5%, then the area of the rectangle will be increased or decreased by how m...
- The length of a rectangle is extended by 26%, while its width is reduced by 26%. What is the percentage change in the area of the rectangle as a result of ...
- The diameter of a sphere is twice the diameter of another sphere, The surface area of the first sphere is equal to the volume of the second sphere, The mag...
Hey! Ask a query
Please enter email id
The email must be a valid email address.
Please enter Mobile Number
Please enter valid Mobile Number
Please enter your Doubt
Think You're Ready for RBI Grade B?
RBI Grade B 2026 Phase 1 Memory Based Paper
- 200 Questions with Detailed Solutions
- Section-wise Coverage (GA, English, Quant & Reasoning)