The following table gives the frequency distribution of marks obtained by $28$ students.

$\begin{array}{ccccc}\text{Marks}& 30& 31& 32& 33\\ \text{Frequency}& 5& 7& 10& 6\end{array}$

Construct the cumulative frequency table for the given data.

The following table gives the marks obtained by the students of a class in an exam out of 50.

$\begin{array}{cc}\text{Marks}& \text{No. of Students}\\ Below10& 5\\ Below20& 10\\ Below30& 23\\ Below40& 31\\ Below50& 40\end{array}$

(i) Convert the cumulative frequency distribution into a regular frequency distribution.

(ii) Find the mean. [3 MARKS]

The following table gives the marks obtained by the students of a class in an exam out of 50.

$\begin{array}{cc}Marks& No.ofStudents\\ Below10& 5\\ Below20& 10\\ Below30& 23\\ Below40& 31\\ Below50& 40\end{array}$

(i) Convert the cumulative frequency distribution into a regular frequency distribution.

(ii) Find the mean.

Given below is a cumulative frequency table:
$\begin{array}{cc}\text{Marks}& \text{Number of students}\\ \text{Below}10& 17\\ \text{Below}20& 22\\ \text{Below}30& 29\\ \text{Below}40& 37\\ \text{Below}50& 50\\ \text{Below}60& 60\end{array}$
Extract a frequency table from the above.