Let $x_1, x_2, \ldots, x_{11}$ be the observations satisfying $\sum_{i=1}^{11}(x_i-4)=22$ and $\sum_{i=1}^{11}(x_i-4)^2=154$. If the mean and variance of the observations are $\alpha$ and $\beta$,then the quadratic equation having the roots $\frac{\alpha}{\beta}$ and $\frac{\beta}{\alpha}$ is

  • A
    $15 x^2-16 x+15=0$
  • B
    $15 x^2-34 x+15=0$
  • C
    $x^2-16 x+60=0$
  • D
    $12 x^2-25 x+20=0$

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