1. **State the problem:** We need to find how many truckloads are required to move a pile of sand shaped like a cone. The cone has a height of 9 yards and a base diameter of 10 yards. Each truck holds 4.71 cubic yards of sand. 2. **Formula for the volume of a cone:** $$V = \frac{1}{3} \pi r^2 h$$ where $r$ is the radius of the base and $h$ is the height. 3. **Calculate the radius:** The diameter is 10 yards, so the radius is half of that: $$r = \frac{10}{2} = 5$$ yards. 4. **Calculate the volume of the cone:** Substitute $r = 5$, $h = 9$, and $\pi = 3.14$ into the formula: $$V = \frac{1}{3} \times 3.14 \times 5^2 \times 9$$ $$V = \frac{1}{3} \times 3.14 \times 25 \times 9$$ $$V = \frac{1}{3} \times 3.14 \times 225$$ $$V = \frac{1}{3} \times 706.5$$ $$V = 235.5$$ cubic yards. 5. **Calculate the number of truckloads:** Each truck holds 4.71 cubic yards, so divide the total volume by the truck capacity: $$\text{truckloads} = \frac{235.5}{4.71}$$ Show cancellation for simplification: $$\text{truckloads} = \frac{\cancel{235.5}}{\cancel{4.71}} = 50$$ 6. **Final answer:** The company will need exactly **50** truckloads to move all the sand.