There are $50$ numbers. Each number is subtracted from $53$ and the mean of the numbers so obtained is found to be $-3.5$. The mean of the given numbers is: (in $.5$)

The weights (in $kg$) of $11$ students are given below:
$37, 42, 40, 39, 41, 35, 37, 36, 40, 40, 42$
Find the median of the data.

Following is the frequency distribution of total marks obtained by the students of different sections of Class $VIII.$

Marks	$100-150$	$150-200$	$200-300$	$300-500$	$500-800$
Number of students	$60$	$100$	$100$	$80$	$180$

Draw a histogram for the distribution above.

The median of the data $78, 56, 22, 34, 45, 54, 39, 54, 84$ is

Find the mean,the median,and the mode of the observations:
$48, 41, 36, 35, 41, 37, 39, 52, 41, 48$

The following table shows a frequency distribution for the speed of cars passing through a particular spot on a highway:

Class interval $(km/h)$	Frequency
$30-40$	$3$
$40-50$	$6$
$50-60$	$25$
$60-70$	$65$
$70-80$	$50$
$80-90$	$28$
$90-100$	$14$

Draw the frequency polygon representing the above data without drawing the histogram.