Attention Math

Class 10 · Chapter 12 · Mensuration

Surface Areas and Volumes

Joining and hollowing solids: what adds, what hides, and what appears.

Source: NCERT Mathematics, Class 10

  1. 12.1Surface Area of a Combined SolidAttention · Look at which surfaces are still exposed after joining.10 min
  2. 12.2Volume of a Combined SolidAttention · Look at the volumes as pieces of space: they simply add.8 min
  3. 12.3Hollowing Out a SolidAttention · Look at the new inside surface the hollow creates.10 min
  4. 12.4Hemispheres: Is the Flat Face There?Attention · Look at the flat face: is it exposed or not?6 min

Problems

The clue is in the question

All 1 problem
  1. 1A cone on a hemisphereA toy is a cone of radius 3.5 cm mounted on a hemisphere of the same radius. The total height of the toy is 15.5 cm. Find the total surface area of the toy. (Use π = 22/7.)Lens · The known factNCERT Ex 12.1 Q3