The following table gives the daily income of 50 workers of a factory:
Daily income (in Rs): | 100-120 | 120-140 | 140-160 | 160-180 | 180-200 |
Number of workers: | 12 | 14 | 8 | 6 | 10 |
Class interval | Mid value(x) | Frequency(f) | fx | Cumulative frequency |
100-120 | 110 | 12 | 1320 | 12 |
120-140 | 130 | 14 | 1820 | 26 |
140-160 | 150 | 8 | 1200 | 34 |
160-180 | 170 | 6 | 1000 | 40 |
180-200 | 190 | 10 | 1900 | 50 |
Total | N=50 |
Mean= =
We have, N= 50,
N/2 = 25
Hence, medium class =120-140, such that
l=120, f’=14, f=12, h=20
Median = l +
Here, we may observe that maximum class frequency is 14 belonging to the class interval 120-140
So, modal class= 120-140
Lower limit, l= 120
f0=12, f2=8, f=14,h = 20
=