The Median of the following discrete series is 

$\begin{array}{r}{x}_i\\ \end{array}$	3	6	5	8	12	7
$f_i$	5	2	4	6	7	6

 

Computation of median 

We have   $N=30\therefore \frac{N}{2}=15$

Cumulative frequency just greater than $N /2$ is $17.$

   The corresponding value of x is 7 

Hence, Median = 7.