The area of a sector of a circle is given by the formula:
\[
\text{Area of sector} = \frac{\theta}{360^\circ} \times \pi r^2
\]
Here, \(r = 7 \, \text{cm}\) and \(\theta = 72^\circ\). Using \(\pi = \frac{22}{7}\), we substitute the values:
\[
\text{Area of sector} = \frac{72}{360} \times \frac{22}{7} \times 7^2 = \frac{1}{5} \times \frac{22}{7} \times 49 = 28.8 \, \text{cm}^2
\]
Thus, the correct answer is option (3).