For some given data,if $\bar{x} + Z = 37.5$ and $\bar{x} - Z = 1.5$,then $M = \ldots$

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

The following table shows the cumulative frequency distribution of marks of $800$ students in an examination:

Marks	Number of students
Below $10$	$10$
Below $20$	$50$
Below $30$	$130$
Below $40$	$270$
Below $50$	$440$
Below $60$	$570$
Below $70$	$670$
Below $80$	$740$
Below $90$	$780$
Below $100$	$800$

Construct a frequency distribution table for the data above.

If $M - \bar{x} = 2$ and $Z = 20.5$,then the median $M = \ldots$ (in $.5$)

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

For some given data,if $Z - M = 12$,then $M - \bar{x} = \ldots \ldots \ldots$