Question

Example 7
The frequency distributsion of the
number of persons and their
respective incomes (in Rs) are given
below. Calculate the median income.
Income (in Rs):
Number of persons:
10
2
20
4
30 40
10 4.​

Answer 1

Answer:

ANSWER:

Families

Monthly income

(X)

Deviation from the Assumed average

(d = X − A) (A = 75)

1

2

3

4

5

6

7

8 70

10

500

75 (A)

13

250

8

42 −5

−65

425

0

−62

175

−67

−33

(N) = 8

(ΣX)=968 Σd = −232 + 600 = 368

where,

N= Number of items

ΣX= Total of monthly income of all the families

Σd= net sum of deviations

Calculation of Mean by Direct Method

X=ΣXN=9688=121

Calculation of mean by short cut method

X=A+ΣdNor, X=75+3688or, X=75+46⇒X=121

So, mean monthly income of a family is Rs 121.

Explanation:

I hope it helps you