Which solid has the least number of faces ?

Options

A. Cylinder
B. Triangular prism
C. Cube
D. Cone

Answer

To determine which solid has the least number of faces, let's analyze the given solids step by step.

### Step 1: Identify the solids and their faces
We have four solids to consider:
1. Cylinder
2. Triangular Prism
3. Cube
4. Cone

### Step 2: Count the faces of each solid
- **Cylinder**: A cylinder has 2 faces. One face is the top circular base, and the other is the bottom circular base.

- **Triangular Prism**: A triangular prism has 5 faces. It has two triangular bases (top and bottom) and three rectangular lateral faces connecting the bases.

- **Cube**: A cube has 6 faces. Each face is a square, and there are six squares in total (top, bottom, and four sides).

- **Cone**: A cone has 1 face. The curved surface is considered one face, and the circular base is not counted as a separate face.

### Step 3: Compare the number of faces
Now, let's summarize the number of faces for each solid:
- Cylinder: 2 faces
- Triangular Prism: 5 faces
- Cube: 6 faces
- Cone: 1 face

### Step 4: Determine the solid with the least number of faces
From the counts above, the cone has the least number of faces, which is 1.

### Final Answer
The solid with the least number of faces is the **cone**.

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