During the medical check up of 35 students of a class, their weights were recorded as follows:
Draw a less than type ogive for the given data. Hence, obtain the median weight from the graph and verify the result by using the formula.
Prepare the table for cumulative frequency for less than type.
Now, draw the less than ogive using suitable points.
Here, $\frac{N}{2}=\frac{\sum f}{2}==\frac{35}{2}=17.5$
From (0, 17.5) draw a line parallel to horizontal axis, which intersects the graph at the point M having x-coordinate as 46.5.
Therefore, the median is 46.5 kg.
Calculation for median using formula.
Now, $\frac{N}{2}=\frac{35}{2}=17.5$
So, 46–48 is the median class.
Here, $l=46, h=2, f=14, F=14$
Median $=l+\frac{\frac{N}{2}-f}{f} \times h$
$=46+\frac{\frac{35}{2}-14}{14} \times 2$
$=46+0.5=46.5 \mathrm{~kg}$
Hence, both the methods give same result.