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Question
Find the mean of the following distribution:
| x | 10 | 30 | 50 | 70 | 89 |
| f | 7 | 8 | 10 | 15 | 10 |
Solution
Calculation of Mean:
| `x_i` | `f_i` | `f_ix_i` |
| 10 | 7 | 70 |
| 30 | 8 | 240 |
| 50 | 10 | 500 |
| 70 | 15 | 1050 |
| 59 | 10 | 890 |
| `sumf_i` = N = 50 | `sumf_ix_i` = 2750 |
∴ Mean = `(sumf_ix_i)/"N"`
= `(2750)/(50)`
= 55.
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