Page 154 - DMGT404 RESEARCH_METHODOLOGY

Research Methodology

Notes Graphical Location of Median

So far we have calculated median by the use of a formula. Alternatively, it can be determined
graphically, as illustrated in the following example.

Example: The following table shows the daily sales of 230 footpath sellers of Chandni
Chowk:

Sales (in Rs.) 0 - 500 500 - 1000 - 1500 - 2000 - 2500 - 3000 - 3500 -
1000 1500 2000 2500 3000 3500 4000
No. of Sellers 12 18 35 42 50 45 20 8

Locate the median of the above data using

1. Only the less than type ogive, and
2. Both, the less than and the greater than type ogives.
Solution:
To draw ogives, we need to have a cumulative frequency distribution.

Class Intervals Frequency Less than c.f. More than c.f.
0 - 500 12 12 230
500 - 1000 18 30 218
1000 - 1500 35 65 200
1500 - 2000 42 107 165
2000 - 2500 50 157 123
2500 - 3000 45 202 73
3000 - 3500 20 222 28
3500 - 4000 8 230 8

1. Using the less than type ogive

Figure 8.2

256

Cumulative Frequency 128
192

64

0 Median = 2080
500 1000 1500 2000 2500 3000 3500 4000
Values

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