Question

Convert the below table into an exclusive series

$\begin{array}{cc}Marks& Frequency\\ 10-14& 4\\ 15-19& 5\\ 20-24& 6\\ 25-29& 3\\ 30-34& 9\end{array}$

• A. $\begin{array}{cc}Marks& Frequency\\ 9.5-14.5& 4\\ 14.5-19.5& 5\\ 19.5-24.5& 6\\ 24.5-29.5& 3\\ 29.5-34.5& 9\end{array}$
• B. $\begin{array}{cc}Marks& Frequency\\ 10-14.5& 4\\ 14.5-19.5& 5\\ 19.5-24.5& 6\\ 24.5-29.5& 3\\ 29.5-34& 9\end{array}$
• C. $\begin{array}{cc}Marks& Frequency\\ 10.5-14.5& 4\\ 14.5-19.5& 5\\ 19.5-24.5& 6\\ 24.5-29.5& 3\\ 29.5-34.5& 9\end{array}$
• D. $\begin{array}{cc}Marks& Frequency\\ 9.5-14.5& 4\\ 14.5-19.5& 5\\ 19.5-24.5& 6\\ 24.5-29.5& 3\\ 29.5-34& 9\end{array}$

Answer 1

The correct option is A $\begin{array}{cc}Marks& Frequency\\ 9.5-14.5& 4\\ 14.5-19.5& 5\\ 19.5-24.5& 6\\ 24.5-29.5& 3\\ 29.5-34.5& 9\end{array}$

To convert the above table into an exclusive series:
a. Difference between the upper limit of class interval and the lower limit of the next class interval = 20-19=1
b. Half the difference is added to upper limit of class interval and half is subtracted from the lower limit of class interval. Hence, 0.5 + 14 = 14.5 and 10 - 0.5 = 9.5.
Likewise, the conversion is done for all the entries in the table.