How many faces are there in a
(i) cuboid, (ii) tetrahedron, (iii) triangular prism, (iv) square pyramid?

Answer

To solve the question of how many faces are there in the given three-dimensional figures, we will analyze each shape step by step.

### Step 1: Count the Faces of a Cuboid
A cuboid is a three-dimensional figure with six rectangular faces.
- The faces can be identified as follows:
- Top face: ABCD
- Bottom face: EFGH
- Four side faces: ABEF, BCFG, CDGH, DAEH
- Therefore, the total number of faces in a cuboid is **6**.

### Step 2: Count the Faces of a Tetrahedron
A tetrahedron is a three-dimensional figure with four triangular faces.
- The faces can be identified as follows:
- Face 1: ABC
- Face 2: ABD
- Face 3: ACD
- Face 4: BCD
- Therefore, the total number of faces in a tetrahedron is **4**.

### Step 3: Count the Faces of a Triangular Prism
A triangular prism has five faces.
- The faces can be identified as follows:
- Two triangular faces: ABC (top) and DEF (bottom)
- Three rectangular faces: ABDE, BCDF, and ACDE
- Therefore, the total number of faces in a triangular prism is **5**.

### Step 4: Count the Faces of a Square Pyramid
A square pyramid has five faces.
- The faces can be identified as follows:
- One square base: ABCD
- Four triangular faces: ABE, ACE, ADE, and BCD
- Therefore, the total number of faces in a square pyramid is **5**.

### Summary of Faces
- Cuboid: **6 faces**
- Tetrahedron: **4 faces**
- Triangular Prism: **5 faces**
- Square Pyramid: **5 faces**