1. **State the problem:** A man whose eyes are 6 ft above the ground sees the top of a pole and the top of a building aligned in a straight line of sight. The pole is 10 ft away and 18 ft tall, and the building is 200 ft away. We need to find the height of the building. 2. **Set up the problem:** Let the height of the building be $h$ ft. 3. **Use similar triangles:** The line of sight from the man's eyes to the top of the pole and building forms two right triangles sharing the same angle of elevation. 4. **Calculate the angle of elevation to the pole's top:** The vertical difference is $18 - 6 = 12$ ft, and the horizontal distance is 10 ft. 5. **Slope of line of sight:** $$\text{slope} = \frac{12}{10} = 1.2$$ 6. **Use the slope to find building height:** The building is 200 ft away, so the vertical difference from the man's eyes to the building top is $$1.2 \times 200 = 240$$ ft. 7. **Calculate building height:** Add the man's eye height: $$h = 6 + 240 = 246$$ ft. **Final answer:** The building is 246 ft tall.