Q1 of 96 Page 157

In the formula for finding the mean of grouped data d_i’s are deviation from a of

We know that, d_i = x_i - a

Where,

_x_i are data and “a” is the assumed mean

i.e. d_i are the deviations from of mid - points of the classes.

While computing mean of grouped data, we assume that the frequencies are

If x_i’s are the mid - points of the class intervals of grouped data, f_i are the corresponding frequencies and is the mean, then is equal to

In the formula for finding the mean of grouped frequency distribution is equal to

The abscissa of the point of intersection of the less than type and of the more than type cumulative frequency curves of a grouped data gives its

In the formula for finding the mean of grouped data di’s are deviation from a of