Question

In the formula `barx = a + (f_i d_i)/f_i`, for finding the mean of grouped data d_i’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

Answer 1

In the formula `barx = a + (f_i d_i)/f_i`, for finding the mean of grouped data d_i’s are deviations from a of mid points of the classes.

Explanation:

We know,

d_i = x_i – a

Where,

x_i are data and ‘a’ is the assumed mean

So, d_i are the deviations from of mid-points of the classes.