1. **State the problem:** Convert 2,640 yards (yd) to miles (mi). 2. **Formula and conversion factor:** We know that 1 mile = 1,760 yards. 3. **Set up the conversion:** $$\text{miles} = \frac{\text{yards}}{\text{yards per mile}} = \frac{2640}{1760}$$ 4. **Simplify the fraction:** $$\frac{2640}{1760} = \frac{\cancel{2640} \div 880}{\cancel{1760} \div 880} = \frac{3}{2}$$ 5. **Evaluate the fraction:** $$\frac{3}{2} = 1.5$$ 6. **Final answer:** $$2,640\ \text{yd} = 1.5\ \text{mi}$$ This means 2,640 yards is equal to 1.5 miles.