Find the mean, and median of the following frequency distribution of ages of $50$ children:

$\begin{array}{|lccccc|}\hline \text{ Age (in years) }& 4-6& 6-8& 8-10& 10-12& 12-14\\ \text{ Number of children }& 3& 8& 20& 12& 7\\ \hline\end{array}$

Using the data given below construct the less than type cumulative frequency table and draw the ogive. From the ogive determine the median.

$\begin{array}{|lcccccccc|}\hline \text{ Marks }& 0-10& 10-20& 20-30& 30-40& 40-50& 50-60& 60-70& 70-80\\ \text{ No. of students }& 3& 8& 12& 14& 10& 6& 5& 2\\ \hline\end{array}$

The following table shows the distribution of the heights of a group of factory workers:

$\begin{array}{|lccccccc|}\hline \text{ Height (in cm) }& 150-155& 155-160& 160-165& 165-170& 170-175& 175-180& 180-185\\ \text{ No. of workers }& 6& 12& 18& 20& 13& 8& 6\\ \hline\end{array}$

Convert the distribution to a more than cumulative frequency distribution and draw its ogive. Hence, obtain the median height from the graph.

The weight of tea in $70$ packets are shown in the following table:

$\begin{array}{|lcccccc|}\hline \text{ Weight (in gram) }& 200-201& 201-202& 202-203& 203-204& 204-205& 205-206\\ \text{ Number of packets }& 13& 27& 18& 10& 1& 1\\ \hline\end{array}$

Draw less than type and more than type ogives for the data and use them to find the median weight.