Find the mode from the following cumulative frequency distribution:

Marks below	$10$	$20$	$30$	$40$	$50$	$60$	$70$	$80$
Number of students	$5$	$11$	$22$	$37$	$56$	$68$	$75$	$80$

(Write the answer upto two decimal places.)

Find the median of the following data:

Find the mean deviation from the mean as well as from the median for the following series:

Find the mean deviation from the mean as well as from the median for the following series:

Find the mean deviation about the median of the following frequency distribution:

(Write the answer upto two decimal places.)

Find the mean deviation from the mean of the following data:

The annual rainfall in $\mathrm{centimetres}$ at a place $A$ over the period $2009$ to $2014$ was as follows:

Examine the mean rainfall and the standard deviation.

The following data relates to the goods produced in a factory. Find the mean and the standard deviation of the daily output of the articles produced.