Question

The mean salaries of 250 workers
in a factory is Rs.95. If the arithmetic
mean of 90 workers in one section is Rs.102.
Find the Arithmetic mean of the
Salary for the other section
​

Answer 1

Explanation:

Find average for following individual data.

2 3 5 6 8 10 11 13 17 20

ANSWER:

Calculating the average using direct method:

Average (X)=ΣXNor, X =2+3+5+6+8+10+11+13+17+2010 or, X =9510⇒X=9.5

Hence, the average of the above individual data is 9.5

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Question 2:

Daily income of 10 families is given as follows:

S. No. 1 2 3 4 5 6 7 8 9 10

Daily Income (in ₹) 100 120 80 85 95 130 200 250 225 275

Calculate average daily income

ANSWER:

Serial No.

Daily Income (in Rs)

(X)

1

2

3

4

5

6

7

8

9

10 100

120

80

85

95

130

200

250

225

275

N=10 ∑X= 1560

Calculating the average daily income using direct method:

Average (X)=∑XNor, X=100+120+80+85+95+130+200+250+225+27510or, X=156010⇒X= Rs 156