Q8 of 44 Page 80

Using assumed mean method find the mean weight of 40 students Using the data given below.

In assumed-mean method, we need to assume a mean value (the near to middle or middlemost value) from xi’s.

We have the following table.



In assumed mean method, arithmetic mean is given by



Where, A = assumed mean = 53


∑fidi = -17


& ∑fi = 40


Putting all these value in the formula, we get



⇒


⇒


Thus, mean weight of 40 students is 52.575 kg.


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