Vegetative propagation is a form of asexual reproduction in plants where new individuals grow from vegetative parts like roots, stems, or leaves rather than seeds. This method ensures rapid growth and identical offspring. It occurs naturally in plants like potatoes (tubers), onions (bulbs), and strawberries (runners). Artificial methods like grafting and layering are also used in horticulture.
Example: A potato tuber contains buds (eyes) that sprout into new plants. Similarly, Bryophyllum reproduces through leaf buds. 

Find the unknown frequency if 24 is the median of the following frequency distribution:
\[\begin{array}{|c|c|c|c|c|c|} \hline \text{Class-interval} & 0-10 & 10-20 & 20-30 & 30-40 & 40-50 \\ \hline \text{Frequency} & 5 & 25 & 25 & \text{$p$} & 7 \\ \hline \end{array}\]