Page 204 - ICSE Math 8

Nested or Combined Solids

Solid figures made up of combination of two or more solids are known as nested solids.
The following are a few examples of nested solids. Find out the solid shapes that have been combined to make
them.

Funnel Pencil Ice cream cone Hut

Visualization of 3D Shapes Through Nets

A net for a 3D shape is like a skeleton outline
in two-dimensions which when folded regains
the three-dimensional shape. This tool helps
in visualizing 3D shapes more clearly.
Let’s perform an activity of cutting open a
cardboard box (3D object) along its edges to
get a net (2D) of the given box (Fig. 18.21)
Nets of various polyhedrons are shown below: Fig. 18.21

Cube Cuboid Triangular prism Hexagonal prism Tetrahedron Square pyramid

EXERCISE 18.1

1. Using Euler’s formula, find the missing numbers.
Faces 6 ?(ii) 8 ?(iv) 5
Vertices ?(i) 6 6 12 ?(v)
Edges 12 9 ?(iii) 30 8

2. Draw the nets for the following solids.
(a) cube (b) cuboid (c) hexagonal prism (d) square pyramid (e) tetrahedron
3. Name the solid shapes in the following nested solids.

(a) (b) (c) (d) (e) (f)
4. Which solids do the following nets represent?

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

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