Organising Data

Here are the ages, $A$ (years), of $40$ people in a cinema.

Show the data in a frequency table with these class intervals: $0\le A<20, 20\le A<40, 40\le A<60$ and $60\le A<80$

Show the data in a frequency table with these class intervals: $A<40, 40\le A<45, 45\le A<50, 50\le A<55, 55\le A<60$ and $60\le A<65$

Compare the table and identify which is the best way to represent the data.

Write your answer with reason.

Julian runs a bookshop. The table shows the number of books purchased by each of his last $25$ customers. 

Calculate the median number of books purchased by these customers. 

Henri plays a game over and over again. On each attempt, he gets a score of between $1$ and $20$. These are his scores for his first seven attempts : $16, 14, 13, 15, 10, 9, 11$. Henri plays the game an eighth time. What is his score if the mean of all $8$ scores is $12$.

The following frequency distribution table shows the number of marks obtained by the students of class $\mathrm{VIII}$ in a test.

What is the total number of students who took the test?

Construct a frequency table from the following data :

Draw a bar graph to illustrate the following :

The marks of $100$ students in a test were recorded as follows :

Convert the above table into an exclusive type frequency distribution and hence make the cumulative frequency table.

The heights (in cm) of $30$ students of $\mathrm{class} \mathrm{IX}$ are given below :

$153, 157, 148, 157, 161, 159, 153, 150, 148, 149, 160, 155, 158, 154, 158, 160, 152, 147, 155, 163, 155, 157, 153, 156, 152, 156, 154, 151, 159, 162.$

Prepare a frequency distribution table with $160 -164, 164 -168,$ as class intervals. Also construct the cumulative frequency table.

The marks in mathematics of $30$ students are as follows :

$75, 44, 53, 61, 58, 88, 37, 60, 64, 84, 78, 98, 59, 68, 58, 60, 55, 70, 48,100, 39, 62, 67, 50, 90, 60, 56, 48, 52, 77.$

How many students have scored less than $50$?

The marks in mathematics of$30$ students are as follows :

$75, 44, 53, 61, 58, 88, 37, 60, 64, 84, 78, 98, 59, 68, 58, 60, 55, 70, 48,100, 39, 62, 67, 50, 90, 60, 56, 48, 52, 77.$

How many students have scored $75$or more?

The marks in mathematics of $30$ students are as follows :

$75, 44, 53, 61, 58, 88, 37, 60, 64, 84, 78, 98, 59, 68, 58, 60, 55, 70, 48,100, 39, 62, 67, 50, 90, 60, 56, 48, 52, 77.$

If $40$are the pass marks, how many students have passed?

The marks in mathematics of $30$ students are as follows :

$75, 44, 53, 61, 58, 88, 37, 60, 64, 84, 78, 98, 59, 68, 58, 60, 55, 70, 48,100, 39, 62, 67, 50, 90, 60, 56, 48, 52, 77.$

What is the lowest score?

The marks in mathematics of 30 students are as follows :

75, 44, 53, 61, 58, 88, 37, 60, 64, 84, 78, 98, 59, 68, 58, 60, 55, 70, 48,100, 39, 62, 67, 50, 90, 60, 56, 48, 52, 77.

What is the highest score?

The marks in mathematics of 30 students are as follows :

$75, 44, 53, 61, 58, 88, 37, 60, 64, 84, 78, 98, 59, 68, 58, 60, 55, 70, 48,100, 39, 62, 67, 50, 90, 60, 56, 48, 52, 77.$

Represent the data in the form of frequency distribution with $30 - 39$ one class, $40 \mathrm{to} 49$ second class and so on.

Using class intervals 0 - 4, 5 - 9, 10 - 14, .... construct the frequency distribution for the following data :

12, 15,8, 16, 13, 7, 4, 12 17. 15, 11, 18, 19, 13, 21, 14,9, 7, 250, 23, 22, 10, 2, 14, 20.

The marks obtained by $40$ students of a class (out of $50$) are given below :$36, 38, 37, 32, 38, 28, 23, 43, 27, 36, 26, 28, 38,36. 33, 43, 32, 25, 41, 21, 27, 43,36, 22, 44. 35, 40, 22,33, 30, 41, 40, 33, 32, 25, 27, 26, 25, 23, 22.$

Create the frequency distribution table for the given data.

The weights of new born babies (in $\mathrm{k}\mathrm{g}$) in a hospital on a particular day are as follows:

$2.3, 2.2, 2.1, 2.7, 2.6, 3.0, 2.5, 2.9, 2.8, 3.1, 2.5, 2.8, 2.7, 2.9, 2.4$

How many babies weigh more than $2.8 \mathrm{k}\mathrm{g}$?

The marks obtained by $40$ students are:

$6,1,7,3,4,2,4,5,6,4,8,3,0,2,3,2,3,3,3,7,9,5,5,8,6,1,2,4,4,0,1,5,9,4,8,1,2,7,3,7$

What is the range of marks?

The marks obtained (out of $10$) by $40$ students are:

$6,1,7,3,4,2,4,5,6,4,8,3,0,2,3,2,3,3,3,7,9,5,5,8,6,1,2,4,4,0,1,5,9,4,8,1,2,7,3,7$

Array the data and form a frequency distribution table.

What is the highest mark?

The ages (in years) of the $40$ teachers in a school are listed here.
$\mathrm{27,} \mathrm{35,} \mathrm{26,} \mathrm{33,} \mathrm{24,} \mathrm{43,} \mathrm{34,} \mathrm{20,} \mathrm{47,} \mathrm{56,} \mathrm{42,} \mathrm{49,} \mathrm{57,} \mathrm{34,} \mathrm{54,} \mathrm{29,} \mathrm{50,} \mathrm{21,} \mathrm{37,} 58,$$\mathrm{30,} \mathrm{28,} \mathrm{26,} \mathrm{20,} \mathrm{34,} \mathrm{33,} \mathrm{27,} \mathrm{41,} \mathrm{59,} \mathrm{47,} \mathrm{62,} \mathrm{52,} \mathrm{29,} \mathrm{30,} \mathrm{25,} \mathrm{37,} \mathrm{29,} \mathrm{44,} 22.$
Which class interval do most teachers belong to?