If the mean of the data $7,8,9,7,8,7, \lambda, 8$ is 8 then variance of the data

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Aicharya · Accepted Answer

Mean $=\frac{7+8+9+7+8+7+\lambda+8}{8}$ $\begin{aligned} & \Rightarrow 8=\frac{54+\lambda}{8} \Rightarrow 64=54+\lambda \Rightarrow \lambda=10 \ & 	ext { Variance }=\frac{\left[\begin{array}{l}(7-8)^2+(8-8)^2+(9-8)^2+(7-8)^2 \ +(8-8)^2+(7-8)^2+(10-8)^2+(8-8)^2\end{array}ight]}{8} \ & \qquad=\frac{1+0+1+1+0+1+4+0}{8}=1 .\end{aligned}$

If the mean of the data $7,8,9,7,8,7, \lambda, 8$ is 8 then variance of the data

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