Q6 of 108 Page 32

Find the mean and variance of frequency distribution given below:

Given, The data is given in table

To Find: Find the mean and, the variance of the frequency


Explanation: Here, the class interval is not continues frequency distribution, So we have to convert into continues frequency distribution by subtracting 0.5 from the lower limit and adding 0.5 to the upper limit then we get,



Now, N=16, ,


Mean






Variance = 3.74


Hence, The variance is 3.74


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