Mean of $5$ observations is $7.$ If four of these observations are $6, 7, 8, 10$ and one is missing then the variance of all the five observations is
Mean of $5$ observations is $7.$ If four of these observations are $6, 7, 8, 10$ and one is missing then the variance of all the five observations is
- [JEE MAIN 2013]
- A
$4$
- B
$6$
- C
$8$
- D
$2$
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- [JEE MAIN 2025]
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