If the mean of $20$ observations is $27.2$,then $\Sigma f_{i} x_{i}$ is ............

The observations $56, 58, 63, x-5, x+1, 75, 81, 85$ have been arranged in ascending order. If the median of the data is $67$,find the value of $x$.

State whether each of the following statements is true or false:
$(1)$ The median of the observations $12, 13, 14, 15, 16$ is $14$.
$(2)$ The mode of the observations $1, 3, 5, 7, 9$ is $5$.

The following is the distribution of the number of employees working on different floors of the six-storey commercial complex:

Floor	$1$	$2$	$3$	$4$	$5$	$6$
Number of employees	$51$	$48$	$42$	$44$	$48$	$32$

Represent the information above by a bar graph.

The observation which is repeated most often in an ungrouped data is called .......... of the data.

If each observation of the data is increased by $5,$ then their mean