Final answer:
Line graphs are often unsuitable because they suggest a continuous relationship between variables. They are not suitable for categorical data or unrelated variables. Other types of graphs such as bar graphs or pie charts are often more appropriate in these cases.
Step-by-step explanation:
A line graph is often unsuitable for certain types of data because it implies a continuous relationship between the variables represented on the x-axis and the y-axis. In situations where data is categorical (not ordered) or where there isn't a clear relationship between variables, line graphs can be misleading.
For instance, if you were trying to display the favorite ice cream flavors of a group of people, a line graph wouldn't be appropriate because the flavors can't be ordered in a meaningful way on an axis. Similarly, line graphs wouldn't be useful for comparing unrelated variables, like the number of rainy days in a month with stock market prices. In these cases, other types of graphs such as bar graphs or pie charts might be more suitable.
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