If the standard deviation of the observations $$ - 5,\, - 4,\, - 3,\, - 2,\, - 1,\,0,\,1,\,2,\,3,\,4,\,5$$ is $$\sqrt {10} .$$ The standard deviation of observations $$15,\,16,\,17,\,18,\,19,\,20,\,21,\,22,\,23,\,24,\,25$$ will be :
A.
$$\sqrt {10} + 20$$
B.
$$\sqrt {10} + 10$$
C.
$$\sqrt {10} $$
D.
None of these
Answer :
$$\sqrt {10} $$
Solution :
The new observations are obtained by adding $$20$$ to each. Hence, $$\sigma $$ does not change.
Releted MCQ Question on Statistics and Probability >> Statistics
Releted Question 1
Select the correct alternative in each of the following. Indicate your choice by the appropriate letter only.
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