Mathematics
Draw a frequency polygon to represent the following data:
| Class-interval | Frequency |
|---|---|
| 0 - 9 | 9 |
| 9 - 18 | 15 |
| 18 - 27 | 6 |
| 27 - 36 | 12 |
| 36 - 45 | 18 |
Answer
Frequency distribution table :
| Class - interval | Class mark | Frequency |
|---|---|---|
| 0 - 9 | 4.5 | 9 |
| 9 - 18 | 13.5 | 15 |
| 18 - 27 | 22.5 | 6 |
| 27 - 36 | 31.5 | 12 |
| 36 - 45 | 40.5 | 18 |
Steps to draw frequency polygon :
Take 2 cm along x-axis = 9 units.
Take 2 cm along y-axis = 5 units.
Find the mid-point of class intervals.
Find points corresponding to given frequencies of classes and the mid-points of class-intervals, and plot them.
Join consecutive points by line segments.
Join first end point with mid-point of class (-9) - 0 with zero frequency and join the other end with mid-point of class 45 - 54 with zero frequency.
The required frequency polygon is shown below:
Related Questions
Find the median for the following data :
Variate Frequency 23 4 26 6 20 13 30 5 28 11 25 4 18 8 16 9 The following table shows the marks obtained by the students of a class in an examination.
Marks No. of students 0 - 10 15 10 - 20 32 20 - 30 55 30 - 40 35 40 - 50 13 Draw a frequency polygon.
The heights of boys in a school are given below :
Height (in cm) Number of boys 140 - 145 24 145 - 150 32 150 - 155 16 155 - 160 20 160 - 165 44 Draw a frequency polygon to represent the above data.
Draw a frequency polygon to represent the following data :
Weight (in kg) No. of workers 35 - 40 6 40 - 45 17 45 - 50 30 50 - 55 8 55 - 60 3