The most efficient representation for communicating the comparative danger of the set of intersections, given the data of intersection locations and associated numbers of accidents, would be a point plot.
A point plot allows for easy comparison of the number of accidents across different intersections, providing a clear visual representation of which locations are more dangerous. It conveys quantitative information effectively and highlights differences in accident numbers, making the data easy to interpret at a glance.
In contrast, pie charts are better for showing proportions, tables can be less visually impactful, and formulas may not effectively communicate comparative danger for this type of data.