Method of Constructing a Frequency Polygon with the Help of a Histogram

We will discuss about the method of constructing a frequency polygon with the help of a histogram.

Step I: Draw the histogram for the frequency distribution as explained above.

Step II: Locate the midpoint of the top horizontal side of each rectangle in the histogram.

Step III: Locate the middle points on the horizontal axis of two imaginary intervals of common size, one before the first class interval and the other after the last class interval.

Step IV: Join all the above midpoints by line segments one after the other in order.

Example: Draw the frequency polygon for the following frequency distribution.

Marks Obtained

Under 20

Under 40

Under 60

Under 80

Under 100

Number of Students

6

10

20

36

50

Solution: Changing the distribution into a continuous distribution of overlapping intervals, we have the following table.

Marks Obtained

0 - 20

20 - 40

40 - 60

60 - 80

80 - 100

Number of Students

6

4

(10 - 6)

10

(20 - 10)

16

(36 - 20)

14

(50 - 36)

The histogram of the distribution is shown in the adjacent figure.

Following steps II, III and IV, the frequency polygon will be as shown alongside.

Scale: On the x-axis, 1 cm = 20 marks.

On the y-axis, 2 mm = 1 student.

From Method of Constructing a Frequency Polygon with the Help of a Histogram to HOME PAGE

Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.

Recent Articles

1. Lines of Symmetry | Symmetry of Geometrical Figures | List of Examples

Aug 10, 24 04:59 PM

Learn about lines of symmetry in different geometrical shapes. It is not necessary that all the figures possess a line or lines of symmetry in different figures.

2. Symmetrical Shapes | One, Two, Three, Four & Many-line Symmetry

Aug 10, 24 02:25 AM

Symmetrical shapes are discussed here in this topic. Any object or shape which can be cut in two equal halves in such a way that both the parts are exactly the same is called symmetrical. The line whi…

Aug 10, 24 01:59 AM

In 6th grade math practice you will get all types of examples on different topics along with the step-by-step explanation of the solutions.

Aug 10, 24 01:57 AM

In 6th Grade Algebra Worksheet you will get different types of questions on basic concept of algebra, questions on number pattern, dot pattern, number sequence pattern, pattern from matchsticks, conce…