Answer:

Write down the number of faces of each of the following figures:

(i) Cuboid

(ii) Cube

(iii) Triangular prism

(iv) Square pyramid

(v) Tetrahedron

ANSWER:

(i) A cuboid has 6 faces, namely ABCD, EFGH, HDAE, GCBF, HDCG and EABF.

(ii) A cube has 6 faces, namely IJKL, MNOP, PLIM, OKJN, LKOP and IJNM.

(iii) A triangular prism has 5 faces (3 rectangular faces and 2 triangular faces), namely QRUT, QTVS, RUVS, QRS and TUV.

(iv) A square pyramid has 5 faces (4 triangular faces and 1 square face), namely OWZ, OWX, OXY, OYZ and WXYZ.

(v) A tetrahedron has 4 triangular faces, namely KLM, KLN, LMN and KMN.

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Question 2:

Write down the number of edges of each of the following figures:

(i) Tetrahedron

(ii) Rectangular pyramid

(iii) cube

(iv) Triangular prism

ANSWER:

(i) A tetrahedron has 6 edges, namely KL, LM, LN, MN, KN and KM.

(ii) A rectangular pyramid has 8 edges, namely AB, AE, AD, AC, EB, ED, DC and CB.

(iii) A cube has 12 edges, namely PL, LK, KO, OP, MN, NJ, JI, IM, PM, LI, ON and KJ.

(iv) A triangular prism has 9 edges, namely QR, RS, QS, TU, TV, UV, QT, RU, and SV.

Answer:

A) 9

B) 6

C) 8

hope this helps you