Classes |
fi |
c.f. |
0 - 100 |
15 |
15 |
100 - 200 |
17 |
32 |
200 - 300 |
f |
32 + f |
300 - 400 |
12 |
44 + f |
400 - 500 |
9 |
53 + f |
500 - 600 |
5 |
58 + f |
600 - 700 |
2 |
60 + f |
From table,
N = 60 + f
⇒ \(\frac N2 =\frac{60 + f}2\)
Median = 240 which lines between class 200 - 300
Median class = 200 - 300
Median = \(l + \left[\frac{\frac N2- c.f.}{f}\right] \times h\)
\(240 = 200 + \left[\frac{\frac {60+f}2- 32}{f}\right] \times 100\)
\(40 = \left[\frac{60 + f - 64}{2f}\right] \times 100\)
\(8f = 10f - 40\)
\(2f = 40\)
\(f =20\)