Frequency Polygons
Frequency polygons show the same information as bar charts, with points joined by lines instead of with vertical bars. Suppose we need to draw a frequency polygon for the data in the table below which contains information about the weights of some ambitious slimmers.
Weight,in kg | Frequency |
12 | |
35 | |
76 | |
80 | |
41 | |
17 |
The frequency polygon is:
Notice that the points are plotted as (midpoint of weight interval, frequency).