For this question, I used a windspeed of 7 mph for Vienna on Day 2, as the question suggests approximation. However, the attached solution used 6 mph, significantly affecting the result. With 7 mph, my final answer is approximately 2.47, which rounds to 2, while the solution gives 3.1, making 3 the closest approximation. This raises the question of the value of approximation, as an 1-point difference can lead to such differences because the whole point of approximation to use numbers that are not exact but close. I’m unsure how this could occur in a real exam. If similar close options arise, how should I determine the appropriate value to use?
“Approximately” in the question refers to the final answer, not the values taken from the graph. If you look closely, the windspeed is clearly 6 mph, as even in the 5-10 section of the graph, there are multiple points with distinct y-positions, and Day 2 is the lowest, indicating 6 mph.