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प्रश्न
The mean of a discrete frequency distribution xi / fi, i = 1, 2, ......, n is given by
पर्याय
`overlineX = (sum f_ix_i)/(sumf_i)`
\[\frac{1}{n} \sum^n_{i = 1} f_i x_i\]
\[\frac{\sum^n_{i = 1} f_i x_i}{\sum^n_{i = 1} x_i}\]
\[\frac{\sum^n_{i = 1} f_i x_i}{\sum^n_{1 = 1} i}\]
उत्तर
The mean of discrete frequency distribution is
`overlineX = (sum f_ix_i)/(sumf_i)`
Hence, the correct option is (a).
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| 5 – 10 | 5 |
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| 25 – 30 | 25 |
| 30 – 35 | 20 |
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| 144 – 148 | 9 |
| 148 – 152 | 24 |
| 152 – 156 | 31 |
| 156 – 160 | 42 |
| 160 – 164 | 64 |
| 164 – 168 | 75 |
| 168 – 172 | 82 |
| 172 – 176 | 86 |
| 176 – 180 | 34 |
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| Below 70 | 670 |
| Below 80 | 740 |
| Below 90 | 780 |
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