The table below shows the salaries of 280 persons
The table below shows the salaries of 280 persons:
| Salary (In thousand Rs.) | No. of persons |
| 5-10 | 49 |
| 10-15 | 133 |
| 15-20 | 63 |
| 20-25 | 15 |
| 25-30 | 6 |
| 30-35 | 7 |
| 35-40 | 4 |
| 40-45 | 2 |
| 45-50 | 1 |
Calculate the median salary of the data.
Answer
| Salary (In thousand Rs.) | No. of persons (f) | cf |
| 5-10 | 49 | 49 |
| 10-15 | 133 | 182 |
| 15-20 | 63 | 245 |
| 20-25 | 15 | 260 |
| 25-30 | 6 | 266 |
| 30-35 | 7 | 273 |
| 35-40 | 4 | 277 |
| 40-45 | 2 | 279 |
| 45-50 | 1 | 280 |
Here, N = 280
N/2 = 280/2 = 140
It is less than 182, hence consider 182 cumulative frequency for the median class.
Median class = 10-15
C = 49. f = 133, l = 10, h = (15 - 10) = 5
Now use the formula,
Median = 10 + (140 - 49)/133 × 5
= 10 + 91 × 5/133
= 13.42
Median salary is Rs.13.42 thousand or Rs.13420.