NIELIT Scientific Assistant A 2020 November: 61

Question

Find the mode of the following data:

$\begin{array}{|l|l||l|l||l||l|l|} \hline   \text{Age} & \text{0-6}& \text{6-12} & \text{12-18} & \text{18-24} & \text{24-30} & \text{30-36} & \text{36-42} \\\hline \text{Frequency} & \text{6} & \text{11}&\text{25} &\text{35}&\text{18}&\text{12}&\text{6} \\ \hline\hline\end{array}$

• A. $20.22$
• B. $19.47$
• C. $21.12$
• D. $20.14$

Answer 1

To find the mode of grouped data we have following formula:

$Mode=l+(\frac{f_1-f_0}{2f_1-f_0-f_2})*h$

where $l$= lower limit of modal class

$h$= size of interval

$f_1$=frequency of modal class

$f_0$=frequency of class preceding the modal class

$f_2$= frequency of class succeeding the modal class

$\therefore \implies mode=18+(\frac{35-25}{2*35-25-18})*6$

$\implies mode=18+(\frac{10}{27})*6$

$\implies mode=20.22$

Option A is correct.

Mode of group data