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प्रश्न
In calculating the mean of grouped data, grouped in classes of equal width, we may use the formula `barx = a + (sumf_i d_i)/(sumf_i)` where a is the assumed mean. a must be one of the mid-points of the classes. Is the last statement correct? Justify your answer.
उत्तर
No, it is not necessary that assumed mean consider as the mid-point of the class interval. It is considered as any value which is easy to simplify it.
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संबंधित प्रश्न
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| Number of women | 2 | 4 | 3 | 8 | 7 | 4 | 2 |
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