The following table gives the daily income of 50 workers of a factory:
Find the mean, mode and median of the above data.
Consider the following table.
Here, the maximum frequency is 14 so the modal class is 120−140.
Therefore,
$l=120$
$h=20$
$f=14$
$f_{1}=12$
$f_{2}=8$
$F=12$
Mean $=\frac{\sum f_{i} x_{i}}{\sum f}$
$=\frac{7260}{50}$
Mean $=145.20$
Thus, the mean daily income of the workers is Rs 145.20.
Median $=l+\frac{\frac{N}{2}-F}{f} \times h$
$=120+\frac{25-12}{14} \times 20$
$=120+\frac{13}{14} \times 20$
$=120+\frac{130}{7}$
Median $=138.57$
Thus, the median of the daily income of the workers is Rs 138.57.
Mode $=l+\frac{f-f_{1}}{2 f-f_{1}-f_{2}} \times h$
$=120+\frac{2}{8} \times 20$
$=120+5$
Mode $=125$
Thus, the mode of the daily income of the workers is Rs 125.