Q14 of 23 Page 15

Find the mean and variance for the following frequency distributions in Exercises.

Presenting the data in the tabular form, we get



We know that Mean,


Where N =


∴


We know that Variance, σ2 =


∴ σ2 = (1/50) × 6600 = 132


Ans. Mean = 27 and Variance = 132

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