The weights (in kg) of 50 wrestlers are recorded in the following table.



Find the mean weight of the wrestlers.

We first find the class mark xi, of each class and then proceed as follows



Assumed mean, (a) = 125


Class width, (h) = 10


and total observations, (N) = 50


By step deviation method,




= 125 - 16


= 123.4kg


Hence, mean weight of wrestlers = 123.4kg


 

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