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प्रश्न
Find the mean of the following data:-
| x | 19 | 21 | 23 | 25 | 27 | 29 | 31 |
| f | 13 | 15 | 16 | 18 | 16 | 15 | 13 |
उत्तर
| x | f | fx |
| 19 | 13 | 247 |
| 21 | 15 | 315 |
| 23 | 16 | 368 |
| 25 | 18 | 450 |
| 27 | 16 | 432 |
| 29 | 15 | 435 |
| 31 | 13 | 403 |
| N = 106 | `sum`fx = 2650 |
Mean `(barx)=(sumfx)/N=2650/106=25`
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| 4 | 10 | A ______ |
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