Page 207 - ICSE Math 8

(b) A point where three faces of a figure meet is known as its:
(i) angle (ii) vertex (iii) edge (iv) none of these

(c) A triangular pyramid is called a:
(i) prism (ii) hexahedron (iii) icosahedron (iv) tetrahedron
(d) A solid having 5 faces, 5 vertices and 8 edges is a:
(i) cube (ii) cuboid (iii) square pyramid (iv) tetrahedron

(e) Each face of an icosahedron is:
(i) a pentagon (ii) a square (iii) a hexagon (iv) an equilateral triangle
(f) The number of vertices in an octagonal pyramid are:
(i) 9 (ii) 10 (iii) 8 (iv) 6
2. Match the Columns.

Column A Column B
(a) Octagonal pyramid (i) 8 vertices
(b) Cube (ii) 30 edges
(c) Hexagonal prism (iii) 12 faces

(d) Icosahedron (iv) 12 vertices
(e) Dodecahedron (v) 9 faces

PRACTICE TIME

1. A solid has 40 faces and 60 edges. How many vertices will it have?
2. Draw nets of cube and triangular prism.
3. Draw a nested solid consisting of:

(a) a cube and a hemisphere (b) a cube and a cuboid
(c) a cylinder and a cone (d) a cone and a hemisphere
(e) two cones (f) two different cubes
4. Add the face that is needed to make the net of:
(a) a square prism (b) a cylinder (c) a rectangular prism

5. For each of the following 3D figures made of cubes, identify the front, side and top views.

Top

(a)

(i) (ii) (iii)
Side
Front

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