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Question
In the formula `barx = a + (f_i d_i)/f_i`, for finding the mean of grouped data di’s are deviations from a of ______.
Options
lower limits of the classes
upper limits of the classes
mid points of the classes
frequencies of the class marks
Solution
In the formula `barx = a + (f_i d_i)/f_i`, for finding the mean of grouped data di’s are deviations from a of mid points of the classes.
Explanation:
We know,
di = xi – a
Where,
xi are data and ‘a’ is the assumed mean
So, di are the deviations from of mid-points of the classes.
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