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Question
The following is the distribution of the size of certain farms from a taluka (tehasil):
| Size of Farms (in acres) |
Number of Farms |
| 5 – 15 | 7 |
| 15 – 25 | 12 |
| 25 – 35 | 17 |
| 35 – 45 | 25 |
| 45 – 55 | 31 |
| 55 – 65 | 5 |
| 65 – 75 | 3 |
Find median size of farms.
Solution
Calculation of the Median size of farms.
| Size of Farms (in acres) |
f | cf |
| 5 – 15 | 7 | 7 |
| 15 – 25 | 12 | 19 |
| 25 – 35 | 17 | 36 |
| 35 – 45 | 25 | 61 |
| 45 – 55 | 31 | 92 |
| 55 – 65 | 5 | 97 |
| 65 – 75 | 3 | 100 |
We have N=100 ⇒ N/2=50
The cumulative frequency just greater than N/2 is 61 and the corresponding class is 35-45.
Thus, 35-45 is the median class such that l =35, f =25, cf =36,h =10.
`Median=l+(N/2-cf)/fxxh`
`=35+(50-36)/25xx10`
`=35+5.6`
`=40.6`
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