Question
Find out the arithmetic mean using the step deviation method.
Hint: In the above problem, cumulative frequencies are given. Firstly, it will be changed into exclusive class interval and thereafter we will calculate arithmetic mean using the step deviation method.
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Item
|
Frequency
|
|
More than 0
|
28
|
|
More than 10
|
24
|
|
More than 20
|
14
|
|
More than 30
|
4
|