Business Statistics

Chapter 3 | Measures of Central Tendency 91

Solution For computing the median, for a continuous frequency distribution we have to

compute cumulative frequencies as shown in Table 3.25.

TABLE 3.25

Computation of median for Example 3.15

Vacations availed Number of employees (f) Cumulative frequency (cf)

0–10 2 2

10–20 18 20

20–30 30 50

30–40 45 95

40–50 35 130

50–60 20 150

60–70 6 156

70-80 3 159

Sum

1

159

=

= =

å

n

i

i

f N

Here N = 159, which is an odd number.

2

=

N

159

79.5

2

=

, which falls in the class 30–40 (see the row of the cumulative

frequency 95 which contains 79.5). Hence the median class is 30–40.

l = lower limit of median class = 30

f = frequency of median ...