Question

The following table records the number of books read by fifteen year old kids. Find the median of the data.

$\begin{array}{cc}\text{No. of books}& \text{Frequency}\\ 0& 2\\ 1& 4\\ 2& 7\\ 3& 4\\ 4& 2\\ 5& 0\\ 6& 1\\ 7& 8\\ 8& 13\\ 9& 7\\ 10& 2\end{array}$

Answer 1

First we have to add the frequencies to find the cumulative frequency as shown in the table :

$\begin{array}{cc}\text{No. of books}& \text{Cumulative Frequency}\\ 0& 2\\ 1& 6\\ 2& 13\\ 3& 17\\ 4& 19\\ 5& 19\\ 6& 20\\ 7& 28\\ 8& 41\\ 9& 48\\ 10& 50\end{array}$

The median number of books read will be given by the 25th or 26th student.

When we start adding the frequencies from 1st, 20th to 28th student read 7 books.

Hence the 25th and 26th student also reads the same number of books

$\Rightarrow$ Median = 7