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प्रश्न
Frequency distribution of daily commission received by 100 salesmen is given below :
|
Daily Commission (in Rs.) |
No. of Salesmen |
| 100-120 | 20 |
| 120-140 | 45 |
| 140-160 | 22 |
| 160-180 | 09 |
| 180-200 | 04 |
Find mean daily commission received by salesmen, by the assumed mean method.
उत्तर
| Daily commission | Classmark |
`d_i = x_i - A` `d_i = x_i - 150` |
No. of salemen `F_i` |
`f_id_i` |
| 100 120 | 110 | -40 | 20 | -800 |
| 120 140 | 130 | -20 | 45 | -900 |
| 140 160 | 150→A | 0 | 22 | 0 |
| 160 180 | 170 | 20 | 09 | 180 |
| 180 200 | 190 | 40 | 04 | 160 |
| `sumf_i = 100` | `sumf_ix_i = -1360` |
`bard = (sumf_id_i)/(sumf)` = `1360/100 = -13.60`
`:. barx = A + bard = 150 + (-13.60) = 136.4`
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