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Class Interval Mean Tutorial

  


Class Interval Arithmetic Mean Definition:
     A range of values of a variable, an interval used in dividing the scale of the variable for the purpose of tabulating the frequency distribution of a sample. In other words, we can define as the individual group of scores in a grouped frequency distribution.

  Formula:

Class Interval Arithmetic Mean :
Arithmetic Mean = ΣfX/Σf
where
              X = Midpoint
              f = Frequency



Class Interval Arithmetic Mean Example: To find the Arithmetic Mean of


IntervalsFrequency(f)
10 - 203
20 - 309
30 - 405


  Step 1: Find Σf.
            Σf = 7

  Step 2:Then, Find the Midpoint for the class interval.
            Midpoint(X) = (10+20)/2, (20+30)/2, (30+40)/2 = 15, 25, 35
  Step 3: Now, Find ΣfX.

            ΣfX =((3*15)+(9*25)+(5*35)) = (45+225+175) = 445


IntervalsFrequency(f)MidpointXf
10 - 203(10 + 20)/2 = 153 * 15 = 45
20 - 309(20 + 30)/2 = 259 * 25 = 225
30 - 405(30 + 40)/2 = 355 * 35 = 175


  Step 4:Now, Substitute in the above formula given.
            Arithmetic mean = ΣfX/Σf = 445/17 = 26.1765

This example will clearly illustrates how to calculate the Class Interval Arithmetic mean manually.



Related Calculator:
>> Class Interval Arithmetic Mean Calculator.

This tutorial will help you dynamically to find the Class Interval Arithmetic Mean problems.