Q. 145.0( 1 Vote )
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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