1. **State the problem:** Tina can till a piece of land in 6 hours, and Tony can do the same in 10 hours. We need to find how long they will take if they work together. 2. **Formula used:** When two people work together, their combined work rate is the sum of their individual work rates. The time taken together is the reciprocal of the combined rate. 3. **Calculate individual rates:** - Tina's rate = $\frac{1}{6}$ (land per hour) - Tony's rate = $\frac{1}{10}$ (land per hour) 4. **Calculate combined rate:** $$\frac{1}{6} + \frac{1}{10} = \frac{5}{30} + \frac{3}{30} = \frac{8}{30} = \frac{4}{15}$$ 5. **Calculate time taken together:** $$\text{Time} = \frac{1}{\text{combined rate}} = \frac{1}{\frac{4}{15}} = \frac{15}{4} = 3.75 \text{ hours}$$ 6. **Convert to hours and minutes:** $$3.75 \text{ hours} = 3 \text{ hours } 0.75 \times 60 = 3 \text{ hours } 45 \text{ minutes}$$ **Final answer:** Tina and Tony working together will take 3 hours and 45 minutes to till the piece of land.