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\ 08-Oct-2025 Bharat Arora Proof-9 Reader’s Sign _______________________ Date __________

Cubes and cuboids can be drawn
on isometric dot paper. Here,
cubes of sides 1 cm, 2 cm and 3
cm are drawn.

(i) (ii) (iii)
Cuboids of different dimensions
are shown. Observe their
dimensions.

(i) (ii) (iii)
iCoSahedroN aNd dodeCahedroN

A solid with 20 triangular faces, is called an icosahedron. Each face
of an icosahedron is an equilateral triangle.
It has 20 faces, 30 edges, 12 vertices. At each vertex, 5 equilateral
triangles meet. Icosahedron Dodecahedron

A solid with 12 faces is called a dodecahedron. In a dodecahedron, each face is a regular
pentagon.

It has 12 faces, 30 edges, 20 vertices. At each vertex, 3 pentagons meet.

practice Time 12a

1. Identify the nets of a cube.

( a) ( b) ( c) ( d)

2. Match the shape to its correct net.
( a) (b) (c) ( d) ( e)

( i) (ii) ( iii) (iv) ( v)

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