Question:
Calculate the median from the following data:
Solution:
First we prepare the following cummulative table to compute the median.
Here, $N=250$
So, $\frac{N}{2}=125$
Thus, the cumulative frequency just greater than 125 is 127 and the corresponding class is $50-60$.
Therefore, $50-60$ is the median class.
Here, $l=50, f=31, F=96$ and $h=10$
We know that
Median $=l+\left\{\frac{\frac{N}{2}-F}{f}\right\} \times h$
$=50+\left\{\frac{125-96}{31}\right\} \times 10$
$=50+\frac{29 \times 10}{31}$
$=50+\frac{290}{31}$
$=50+9.35$
$=59.35$
Hence, the median is 59.35.