The diameter of a circle is 28 cm. Find its :
area

Answer

To find the area of a circle when the diameter is given, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Diameter**:
The diameter of the circle is given as 28 cm.

2. **Calculate the Radius**:
The radius (r) is half of the diameter.
\[ r = \frac{d}{2} = \frac{28 \text{ cm}}{2} = 14 \text{ cm} \]

3. **Use the Area Formula**:
The area (A) of a circle is given by the formula:
\[ A = \pi r^2 \]

4. **Substitute the Radius into the Formula**:
Now substitute the radius into the area formula. Using \(\pi \approx \frac{22}{7}\):
\[ A = \pi (14 \text{ cm})^2 = \frac{22}{7} \times (14 \times 14) \]

5. **Calculate \(14^2\)**:
First, calculate \(14^2\):
\[ 14^2 = 196 \]

6. **Substitute Back into the Area Formula**:
Now substitute \(196\) back into the area formula:
\[ A = \frac{22}{7} \times 196 \]

7. **Simplify the Calculation**:
To simplify, notice that \(196\) can be divided by \(7\):
\[ 196 \div 7 = 28 \]
So now we have:
\[ A = 22 \times 28 \]

8. **Calculate \(22 \times 28\)**:
Now calculate \(22 \times 28\):
\[ 22 \times 28 = 616 \]

9. **Final Result**:
Therefore, the area of the circle is:
\[ A = 616 \text{ cm}^2 \]