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Root Mean Square(RMS)/Quadratic Mean(QM) Tutorial

  


Root Mean Square(RMS)/Quadratic Mean(QM) Definition:
     Square root of the mean square value of a random variable. In otherwords, we can define the root mean square is a statistical measure of the magnitude of a varying quantity. It can be calculated for a series of discrete values or for a continuously varying function. It is also known as Quadratic Mean(QM).

Root Mean Square/Quadratic Mean Formula:
Root Mean Square/Quadratic Mean = Sqrt((X1)2+(X2)2+(X3)2+........+(XN)2/N)
where
              X = Individual score
              N = Sample size (Number of scores)



Root Mean Square(RMS) Example: To find the Root Mean Square of -2,-1,-3,1,5.

  Step 1: Count the total number of values.
            N = 5

  Step 2: Square all the values.
            4,1,9,1,25

  Step 3: Take the average of the square values.
            4+1+9+1+25/5 = 40/5 = 8

  Step 4: Take the square root of the average values.
            RMS/QM = sqrt(8) = 2.83


This example will guide you to calculate the Root mean square/Quadratic Mean manually.



Related Calculator:
>> Root Mean Square(RMS)/Quadratic Mean(QM) Calculator.

This tutorial will help you dynamically to find the Root Mean Square(RMS)/Quadratic Mean(QM) problems.