Q8 of 145 Page 407

While calculating the mean of a given data by the Assumed - mean method, the following values were obtained:

A = 25, = 110, = 50.


Find the mean.

We have got

A = 25, Σfi = 50 & Σfidi = 110


∵ By Assumed - mean method, mean is given by



⇒


⇒


Thus, mean is 27.2


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