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

The following frequency distribution gives the monthly consumption of electricity of $68$ consumers of a locality. Find the median,mean,and mode of the data and compare them.

Monthly consumption (in units)	Number of consumers
$65-85$	$4$
$85-105$	$5$
$105-125$	$13$
$125-145$	$20$
$145-165$	$14$
$165-185$	$8$
$185-205$	$4$

The marks distribution of $30$ students in a mathematics examination is given in the table. Find the mode of this data. Also,compare and interpret the mode and the mean.

Class interval	$10-25$	$25-40$	$40-55$	$55-70$	$70-85$	$85-100$
Number of students	$2$	$3$	$7$	$6$	$6$	$6$

$\frac{Z-M}{M-\bar{x}}=\ldots \ldots \ldots \ldots$

Consider the following frequency distribution of the heights of $60$ students of a class:

Height (in $cm$)	Number of students
$150-155$	$15$
$155-160$	$13$
$160-165$	$10$
$165-170$	$8$
$170-175$	$9$
$175-180$	$5$

The sum of the lower limit of the modal class and upper limit of the median class is:

For some given data, if $M = 15.4$ and $\bar{x} = 14.5$, then $Z = \dots$