
A.
(sqrt{2}) 
B.
(sqrt{3}) 
C.
(sqrt{6}) 
D.
(sqrt{10})
Correct Answer: Option A
Explanation
Mean x = (frac{sum x}{n})
( = frac{5 + 4 + 3 + 2 + 1}{5})
( = frac{15}{5})
= 3
(begin{array}{cc}
x & d = x – 3 & d^2 \
hline
5 & 2 & 4 \
4 & 1 & 1 \
3 & 0 & 0 \
2 & 1 & 1 \
1 & 2 & 4 \
hline
& & sum d^2 + 10
end{array})
Hence, standard deviation;
( = sqrt{frac{sum d^2}{n}} = sqrt{frac{10}{5}})
( = sqrt{2})
There is an explanation video available below.