Frequency polygon is also a graphical representation of data, where the frequency is plotted against midpoint of the class interval. The frequencies corresponding to the mid points of class intervals are joined by line segments to get the frequency polygon.
A frequency polygon is drawn by drawing a histogram for the given data and joining the midpoints of the top of the rectangles. It can be drawn by marking the midpoints of the class intervals corresponding to their respective frequencies and joining them by line segments.
Construct frequency polygon for the following data :
|CI||5 – 10||10 – 15||15 – 20||20 – 25||25 – 30||30 – 35||35 – 40||40 – 45|