Select Board & Class

Login

Statistics

Question 1:

The following frequency distribution gives the monthly consumption of electricity of 68 consumers of a locality. Find the median, mean and mode of the data and compare them.

Monthly consumption (in units)

Number of consumers

65 − 85

4

85 − 105

5

105 − 125

13

125 − 145

20

145 − 165

14

165 − 185

8

185 − 205

4

Answer:

To find the class marks, the following relation is used.

Taking 135 as assumed mean (a), di, ui, fiui are calculated according to step deviation method as follows.

Monthly consumption (in units)

Number of consumers (f i)

xi class mark

di= xi− 135

65 − 85

4

75

− 60

− 3

− 12

85 − 105

5

95

− 40

− 2

− 10

105 − 125

13

115

− 20

− 1

− 13

125 − 145

20

135

0

0

0

145 − 165

14

155

20

1

14

16...

To view the solution to this question please

What are you looking for?

Syllabus