1. **State the problem:** Ava has £4.72 in her wallet and £17.05 in her money box. She receives an additional £19 for her birthday. We need to find the most expensive game she can buy from the list given her total money. 2. **Calculate total money Ava has:** $$\text{Total money} = 4.72 + 17.05 + 19 = 40.77$$ 3. **List the game prices:** - Erdős’ Number Mystery: £25 - True or False: Disappearance of Boole: £30 - Newton’s Apple Picker: £35 - Euclidean Space Wars: £40 - Program Pioneer: £45 - Turing’s Enigma: £50 4. **Determine the most expensive game Ava can afford:** She can buy any game priced at or below £40.77. 5. **Compare prices to total money:** - £25 ≤ £40.77 (can buy) - £30 ≤ £40.77 (can buy) - £35 ≤ £40.77 (can buy) - £40 ≤ £40.77 (can buy) - £45 > £40.77 (cannot buy) - £50 > £40.77 (cannot buy) 6. **Conclusion:** The most expensive game Ava can buy is **Euclidean Space Wars** priced at £40. **Final answer:** Euclidean Space Wars