Find the mean and variance for the data 6, 7, 10, 12, 13, 4, 8, 12

Asked by Abhisek | 1 year ago |  77

##### Solution :-

$$Mean , \overline{X} = \dfrac{\displaystyle\sum_{i=1}^{a} X_i}{n}$$

So, x̅ = $$\dfrac{ (6 + 7 + 10 + 12 + 13 + 4 + 8 + 12)}{8}$$

$$\dfrac{72}{8}$$

= 9

Let us make the table of the given data and append other columns after calculations. We know that Variance,

$$σ^2= \dfrac{1}{N} \displaystyle\sum_{i=1}^{a} f_i (X_i-\overline {X} )^2$$

σ2$$\dfrac{1}{8}\times 74$$

= 9.2

Mean = 9 and Variance = 9.25

Answered by Pragya Singh | 1 year ago

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