The dimaeter of the base of a cylinder is 7 cm and height is 5 cm. Find its curved surface area.

Answer

To find the curved surface area of a cylinder, we can use the formula:

**Curved Surface Area (CSA) = 2πrh**

Where:
- r = radius of the base of the cylinder
- h = height of the cylinder
- π (pi) is approximately 22/7 or 3.14

**Step-by-Step Solution:**

1. **Identify the Diameter and Calculate the Radius:**
- Given diameter of the base = 7 cm.
- Radius (r) = Diameter / 2 = 7 cm / 2 = 3.5 cm.

2. **Identify the Height:**
- Given height (h) = 5 cm.

3. **Substitute the Values into the Curved Surface Area Formula:**
- CSA = 2πrh
- Substitute r = 3.5 cm and h = 5 cm into the formula:
- CSA = 2 × (22/7) × (3.5) × (5).

4. **Calculate the Curved Surface Area:**
- First, calculate 2 × (22/7):
- 2 × (22/7) = 44/7.
- Now, multiply by the radius and height:
- CSA = (44/7) × (3.5) × (5).
- Convert 3.5 to a fraction: 3.5 = 7/2.
- So, CSA = (44/7) × (7/2) × (5).
- The 7 in the numerator and denominator cancels out:
- CSA = (44/2) × 5 = 22 × 5 = 110 cm².

5. **Final Answer:**
- The curved surface area of the cylinder is **110 cm²**.

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