For some given data,if $M = 62.5$ and $\bar{x} = 64$,then $Z = \ldots$

The formula $\ldots \ldots$ represents the empirical relationship between the measures of central tendency.

In the formula $M = l + \frac{(\frac{n}{2} - cf)}{f} \times c$ for the median,$cf = \ldots \ldots \ldots$

Given below is a cumulative frequency distribution showing the marks secured by $50$ students of a class:

Marks	Below $20$	Below $40$	Below $60$	Below $80$	Below $100$
Number of students	$17$	$22$	$29$	$37$	$50$

Form the frequency distribution table for the data.

For a given frequency distribution,$\Sigma f_{i} u_{i} = -13$,$n = \Sigma f_{i} = 100$,$A = 62.5$ and $c = 15$. Then,mean $\bar{x} = \dots$

For a given frequency distribution,$n=100, A=20$ and $\bar{x}=20$. Then,$\Sigma f_{i} d_{i}=\ldots \ldots \ldots . .$