Let the mean and variance of $8$ numbers $x , y , 10$, $12,6,12,4,8$, be $9$ and $9.25$ respectively. If $x > y$, then $3 x-2 y$ is equal to $...........$.
Let the mean and variance of $8$ numbers $x , y , 10$, $12,6,12,4,8$, be $9$ and $9.25$ respectively. If $x > y$, then $3 x-2 y$ is equal to $...........$.
- [JEE MAIN 2023]
- A
$24$
- B
$25$
- C
$23$
- D
$22$
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$\mathrm{x}$
$-2$
$-1$
$3$
$4$
$6$
$\mathrm{P}(\mathrm{X}=\mathrm{x})$
$\frac{1}{5}$
$\mathrm{a}$
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$\frac{1}{5}$
$\mathrm{~b}$
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| $\mathrm{x}$ | $-2$ | $-1$ | $3$ | $4$ | $6$ |
| $\mathrm{P}(\mathrm{X}=\mathrm{x})$ | $\frac{1}{5}$ | $\mathrm{a}$ | $\frac{1}{3}$ | $\frac{1}{5}$ | $\mathrm{~b}$ |
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