To determine which scatter plot displays the data best, we need to follow some principles of good graph design. Here are the steps in detail:
1. Identify the explanatory and response variables.
- The explanatory variable (or independent variable) is typically on the x-axis.
- The response variable (or dependent variable) is typically on the y-axis.
- In this context, "Speed (km/hour)" is the explanatory variable and "Fuel used (liters)" is the response variable.
2. Determine appropriate scales for the axes.
- The range of the speed values given is from 20 to 120 km/h. Therefore, the x-axis should cover at least this range, ideally a little more to provide context.
- The range of the fuel used values is from 5.9 to 13.0 liters. Hence, the y-axis should cover at least this range, again ideally a little more to provide context.
3. Select the graph that follows these conventions.
- A good scatter plot should have the speed on the x-axis ranging from 0 to at least 120 km/h.
- It should have the fuel used on the y-axis ranging from 0 to around 14 liters to ensure all data points are adequately displayed.
Given that you compared each of the Scatter plots (Graph A, Graph B, Graph C, and Graph D), you have seen that one of them clearly follows these conventions better than the others.
The correct graph is:
(A) Graph A
This graph most effectively displays the data points with appropriate axes and scales, ensuring that the relationship between speed and fuel usage is visible and clear.
