Let us now plot the points corresponding to the ordered pairs given by (38,0),(40,3),(42,5),(44,9),(46,14),(48,28),(50,32) and (52,35) on a graph paper and join them by a free hand smooth curve.
Now,
Weight (in kg) Number of students (Frequency)
0-38 0
38-40 3
40-42 2
42-44 4
44-46 5
46-48 14
48-50 4
50-52 3
Mode: The class which have highest frequency. In this case, class interval 46-48 is the modal class.
Now, Lower limit of modal class, l=46, h=2, f1=14, f0=5, f2=4
We know that,
Mode = l + ((f1-f0)/(2f1-f0-f2)) * h
= 46 + ((14-5)/(2(14)-5-4)) * 2
= 46 + (9/19) * 2
= 46 + 0.95
Mode = 46.95, verified.