MCQ
If the data $x_1, x_2, ...., x_{10}$ is such that the mean of first four of these is $11$, the mean of the remaining six is $16$ and the sum of squares of all of these is $2,000$; then the standard deviation of this data is
- A$2\sqrt 2 $
- ✓$2$
- C$4$
- D$\sqrt 2 $