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प्रश्न
The following table shows the income of farmers in a grape season. Find the mean of their income.
|
Income
(Thousand Rupees)
|
20 - 30 | 30 - 40 | 40 - 50 | 50 - 60 | 60 - 70 | 70 - 80 |
| Farmers | 10 | 11 | 15 | 16 | 18 | 14 |
उत्तर
|
Class
(Income in thousand rupees) |
Class Mark xi |
Frequency (Number of farmers) fi |
Class mark × Frequency xifi |
| 20 - 30 | 25 | 10 | 250 |
| 30 - 40 | 35 | 11 | 385 |
| 40 - 50 | 45 | 15 | 675 |
| 50 - 60 | 55 | 16 | 880 |
| 60 - 70 | 65 | 18 | 1170 |
| 70 - 80 | 75 | 14 | 1050 |
| \[\sum_{} f_i = 84\] | \[\sum_{} x_i f_i = 4410\] |
Mean = \[\frac{\sum_{} x_i f_i}{\sum_{} f_i}\]
= `4410/84`
= 52 . 5 thousand rupees
= 52500
Hence, the mean of the income is Rs 52500.
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