The distribution below gives the weights of 30 students of a class. Find the median weight of the students. \begin{array}{|c|c|c|c|c|c|c|} \hline \text{Weight (in kg)} & 40 - 45 & 45 - 50 & 50 - 55 & 55 - 60 & 60 - 65 & 70 - 75 \\ \hline \text{Number of students} & 2 & 3 & 8 & 6 & 3 & 2 \\ \hline \end{array}