The outcome of each of $30$ items was observed; $10$ items gave an outcome $\frac{1}{2} - d$ each, $10$ items gave outcome $\frac {1}{2}$ each and the remaining $10$ items gave outcome $\frac{1}{2} + d$ each. If the variance of this outcome data is $\frac {4}{3}$ then $\left| d \right|$ equals
The outcome of each of $30$ items was observed; $10$ items gave an outcome $\frac{1}{2} - d$ each, $10$ items gave outcome $\frac {1}{2}$ each and the remaining $10$ items gave outcome $\frac{1}{2} + d$ each. If the variance of this outcome data is $\frac {4}{3}$ then $\left| d \right|$ equals
- [JEE MAIN 2019]
- A
$\frac {2}{3}$
- B
$2$
- C
$\frac {\sqrt 5}{2}$
- D
$\sqrt 2$
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The variance $\sigma^2$ of the data is $ . . . . . .$
$x_i$
$0$
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- [JEE MAIN 2024]
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