The paper contains two (2) sections, section A and section B. From section A answer all questions (40 Marks). Section B: Answer Any five (5) Questions.

Since the value of $\sqrt{72}$ is not provided and cannot be expressed in terms of $\sqrt{5}$ or $\sqrt{7}$, we calculate its numerical value.

$$\sqrt{72} \approx 8.485281$$

$$\frac{3}{\sqrt{7}} = \frac{3}{2.6458}$$ $$\frac{3}{2.6458} \approx 1.133879$$

$$\sqrt{72} - \frac{3}{\sqrt{7}} \approx 8.485281 - 1.133879$$ $$8.485281 - 1.133879 = 7.351402$$

The result 7.351402 rounded to four significant figures is 7.351.

$$\boxed{\text{7.351}}$$