Grouping Data and Histogram

Prepare a continuous frequency distribution table by taking a class interval of $7$ from the following data.

$28, 17, 15, 22, 29, 21, 23, 27, 18, 12, 7, 2, 9, 4, 1, 8, 3, 10, 5, 20, 16, 12, 8, 4, 33, 27, 21, 15, 3, 36, 27, 18, 9, 2, 4, 6, 32, 31, 29, 18, 14, 13, 15, 11, 9, 7, 1, 5, 37, 32, 28, 26, 24, 20, 19, 25, 19, 20, 6, 9$

Construct a frequency distribution table for given data:

$10,12,15,20,23,30,35,38,22,29,13,17,33,36,40$

The marks of  $20$ students of a class are given:

$81 92 73 100 99 85 78 92 90 83 80 73 84 72 70 95 82 70 91 79$

Construct a frequency distribution table.

The age of $18$ members in a Yoga Institute are given:

$45,25,10,55,60,65,35,45,32,29,31,37,40,56,22,28,36,40$

If number of classes is $11$, identify the width of each class.

The marks of students in a class is given:

$34,99,100,89,37,39,67,56,76,91,50,65,70,95,85,61,72,78,84,92$

Identify the width of each class if number of class is $10$

Identify the scale used in the histogram given below.

Write any one difference between a histogram and a bar graph.

A histogram is drawn for discrete 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 $12$.

Calculate the mean mark for the data in the table.

Write your answer up to two decimal places.

The weights $\left(\mathrm{in} \mathrm{kg}\right)$ of $30$ students of a class are

$39,43,32,37,29,26,31,45,46,31,37,38,30,39,36,41,35,34,41,46,39,38,36,38,40,42,33,43,44,33$

Prepare a frequency distribution table using one class interval as $30-35$, in which $30$ is included and $35$ excluded. Which class interval has highest frequency.

The ages (in years) of $360$ patients treated in a hospital on a particular day are given below:

Which age group has the highest number of patients.

The following table shows the number of illiterate persons in the age group ($10-58$ years) in a town. How many illiterates are there in the age group $34-42$.

Find the size of the class interval:
$$\begin{gathered} 200 - 220 \\ 220 - 240 \\ 240 - 260 \\ 260 - 280 \end{gathered}$$

Find the size of the class interval in the following caes.
$0 - 10$
$10 - 20$
$20 - 30$
$30 - 40$

Find the size of the class interval.

 Draw a histogram and hence estimate the mode for the following frequency distribution:

$\begin{array}{|lcccccc|}\hline \text{ Class }& 0-10& 10-20& 20-30& 30.-40& 40-50& 50-60\\ \text{ Frequency }& 2& 8& 10& 5& 4& 3\\ \hline\end{array}$

The histogram given alongside is based on the number of hours $30$ students spent outdoors on a Sunday. How many students spent more than four hours outdoors?