The mean and variance of seven observations are $8$ and $16$, respectively. If $5$ of the observations are $2, 4, 10, 12, 14,$ then the product of the remaining two observations is

  • [JEE MAIN 2019]
  • A

    $40$

  • B

    $45$

  • C

    $49$

  • D

    $48$

Similar Questions

The following values are calculated in respect of heights and weights of the students of a section of Class $\mathrm{XI}:$

  Height Weight
Mean $162.6\,cm$ $52.36\,kg$
Variance $127.69\,c{m^2}$ $23.1361\,k{g^2}$

Can we say that the weights show greater variation than the heights?

The mean and standard deviation of the marks of $10$ students were found to be $50$ and $12$ respectively. Later, it was observed that two marks $20$ and $25$ were wrongly read as $45$ and $50$ respectively. Then the correct variance is $............$.

  • [JEE MAIN 2023]

Find the mean and variance for the first $10$ multiples of $3$

Let $\mu$ be the mean and $\sigma$ be the standard deviation of the distribution 

$X_i$ $0$ $1$ $2$ $3$ $4$ $5$
$f_i$ $k+2$ $2k$ $K^{2}-1$ $K^{2}-1$ $K^{2}-1$ $k-3$

where $\sum f_i=62$. if $[x]$ denotes the greatest integer $\leq x$, then $\left[\mu^2+\sigma^2\right]$ is equal $.........$.

  • [JEE MAIN 2023]

The mean and standard deviation of a group of $100$ observations were found to be $20$ and $3,$ respectively. Later on it was found that three observations were incorrect, which were recorded as $21,21$ and $18 .$ Find the mean and standard deviation if the incorrect observations are omitted.