1. **State the problem:** We have a map scale of 1cm : 4 kilometres. The actual distance between two cities is 52 kilometres. We need to find the distance between the cities on the map in cm. 2. **Formula used:** The scale means: $$\text{Map distance} = \frac{\text{Actual distance}}{\text{Scale factor}}$$ 3. **Apply the formula:** $$\text{Map distance} = \frac{52}{4}$$ 4. **Simplify the fraction:** $$\text{Map distance} = \cancel{\frac{52}{4}} = 13$$ 5. **Interpretation:** The distance between the cities on the map is 13 cm. **Final answer:** 13 cm