can anyone explain me frequency polygon with examples nicely
Answers
A frequency polygon is almost identical to a histogram, which is used to compare sets of data or to display a cumulative frequency distribution. It uses a line graph to represent quantitative data.
To draw frequency polygons, we begin with, drawing histograms and follow the following steps:
Step 1- Choose the class interval and mark the values on the horizontal axes
Step 2- Mark the mid value of each interval on the horizontal axes.
Step 3- Mark the frequency of the class on the vertical axes.
Step 4- Corresponding to the frequency of each class interval, mark a point at the height in the middle of the class interval
Step 5- Connect these points using the line segment.
Step 6- The obtained representation is a frequency polygon.
Example 1: In a batch of 400 students, the height of students is given in the following table. Represent it through a frequency polygon.
Solution: Following steps are to be followed to construct a histogram from the given data:
The heights are represented on the horizontal axes on a suitable scale as shown.
The number of students is represented on the vertical axes on a suitable scale as shown.
Now rectangular bars of widths equal to the class- size and the length of the bars corresponding to a frequency of the class interval is drawn.
Frequency polygons can also be drawn independently without drawing histograms. For this, the midpoints of the class intervals known as class marks are used to plot the points.
