The following series relates to the daily income of workers employed in a firm. Compute (a) highest income of lowest 50% workers (b) minimum income earned by the top 25% workers and (c) maximum income earned by lowest 25% workers.
|
Daily Income (in Rs) |
10 – 14 |
15 – 19 |
20 – 24 |
25 – 29 |
30 – 34 |
35 – 39 |
|
Number of workers |
5 |
10 |
15 |
20 |
10 |
5 |
|
Daily Income (in Rs) Class Interval |
No. of Workers (f) |
Cumulative frequency (CF) |
|
9.5 – 14.5 |
5 |
5 |
|
14.5 – 19.5 |
10 |
15 |
|
19.5 – 24.5 |
15 |
30 |
|
24.5 – 29.5 |
20 |
50 |
|
29.5 – 34.5 |
10 |
60 |
|
34.5 – 39.5 |
5 |
65 |
|
|
|
|
(a) Highest income of lowest 50% workers
32.5th item lies in the 50th cumulative frequency and the corresponding class interval is 24.5 – 29.5.
(b) Minimum income earned by top 25% workers
16.25th item lies in the 30th cumulative frequency and the corresponding class interval is 19.5 – 24.5
(c) Maximum income earned by lowest 25% workers,
48.75th item lies in 50th item and the corresponding class interval is 24.5 – 29.5.
