A frequency polygon is a graph used to visually represent a frequency table where at least one of the scales represents continuous data.
A frequency polygon is produced by joining the midpoints of the tops of the bars in a histogram. The ends of the polygon are joined to the horizontal axis at the appropriate end of each interval.
Below is a list of results (in percent) of twenty students on a mathematics examination.
38, 46, 50, 55, 57, 62, 64, 65, 66, 68, 68, 72, 73, 76, 77, 77, 79, 80, 88, 93
One possible frequency table of these results is shown below.
A histogram based on the frequency table is shown below.
A frequency polygon created from the histogram is shown below.
