Question

Find the value of p if the median is 50. Plz answer it

Answer 1

We know that to calculate Median we have to create CF column

$\begin{table}[] \begin{tabular}{|l|l|l|} \cline{1-3} Class & \begin{tabular}[c]{@{}l@{}}Frequency\\ fi\end{tabular} & (CF) \\ \cline{1-3} 20-30 & 25 & 25 \\ \cline{1-3} 30-40 & 15 & 40 \\\cline{1-3} 40-50 & p & 40+p \\ \cline{1-3} 50-60 & 6 & 46+p \\ \cline{1-3} 60-70 & 24 & 70+p \\\cline{1-3} 70-80 & 12 & 82+p \\ \cline{1-3} 80-90 & 8 & 90+p \\ \cline{1-3} Total & & \\ \cline{1-3} \end{tabular} \end{table}$

We know that Median of grouped data can be calculated as

$Median= l + \bigg(\frac{ \frac{n}{2} - CF}{f} \bigg) \times h$
Since Median is 50; so median class is 50-60

$50 = 50+ (\frac{ \frac{90 + p}{2} - 40 - p}{6} ) \times 10 \\ \\ 0 = \frac{90 + p - 80 - 2p}{12} \times 10 \\ \\ = - p = - 10 \\ \\ p = 10$
Thus p = 10

Hope it helps you.