Q.
Find median from the following distribution :
Class
Frequency
5 - 10
5
10 - 15
6
15-20
15
20-25
10
25-30
5
30-35
4
35-40
2
40-45
2
| Class | Frequency |
|---|---|
| 5 - 10 | 5 |
| 10 - 15 | 6 |
| 15-20 | 15 |
| 20-25 | 10 |
| 25-30 | 5 |
| 30-35 | 4 |
| 35-40 | 2 |
| 40-45 | 2 |
Statistics
Solution:
Class
$f_i$
$C .F$ .
5 - 10
5
5
10 - 15
6
11
15-20
15
26
20-25
10
36
25-30
5
41
30-35
4
45
35-40
2
47
40-45
2
49
$\frac{ N }{2}=\frac{49}{2}=24.5$
Median class is $(15-20)$
As, Median $=15+\frac{24.5-11}{15} \times 5$
$=15+\frac{13.5}{3}=15+4.5=19.5$
| Class | $f_i$ | $C .F$ . |
|---|---|---|
| 5 - 10 | 5 | 5 |
| 10 - 15 | 6 | 11 |
| 15-20 | 15 | 26 |
| 20-25 | 10 | 36 |
| 25-30 | 5 | 41 |
| 30-35 | 4 | 45 |
| 35-40 | 2 | 47 |
| 40-45 | 2 | 49 |