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Look at the objects in the picture carefully and name them using the clues for
solid shapes given below:
1. A solid with 1 curved face, 1 flat face and 1 corner is a __________ .

2. A solid with 2 flat faces, one curved face and 2 edges is a __________ .
3. A solid with 12 edges and equal opposite faces is a __________ .
4. A solid with 1 face and no corners is a __________ .

5. A solid with 8 corners and 6 equal faces is a __________ .
6. A solid with 1 flat face, 1 curved face and no corner is a __________ .

Solid ShApeS

We know that a cube, cuboid, sphere, cylinder, cone, etc. are solids. Solids are called
3-dimensional (3D) shapes as these have length, width and height (depth).
The surface of a solid shape is called a face. The line where two faces meet is called
an edge. The point where three edges meet is called a corner or vertex.

Now, we will explore some solids.

Cube Cuboid Sphere
Vertex Vertex Face
Edge Edge
Face Face

6 faces, 12 edges, 8 vertices 6 faces, 12 edges, 8 vertices 1 face (curved)
All the faces of a cube are All the faces of a cuboid are A sphere has no vertex and no
squares of the same size. rectangles. Only opposite faces
are equal. edge.
hemisphere Cylinder Cone

Edge Face Edge Place
Place Face Face
Curved Curved
Face Face
Curved Face Edge Vertex
2 faces (1 curved and 1 plane) 3 faces (2 plane and 1 curved) 2 faces (1 curved and 1 plane),
and 1 edge and 2 edges 1 edge and 1 vertex

Combination of Blocks

example. How many cubes are there in each of these cube towers?

a. b.

Solution. a. There are 27 cubes. b. There are 33 cubes.

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Mathematics 4 Geometry