Find the standard deviation of the sample data set. 127 135 128 131 133 127 1Find the standard deviation of the sample data set. 127 135 128 131 133 127 122 4.0 2.0 4.4 19.0
Answers
In the first set, the standard deviation is: 11.67
The mean is 130.67.
(130.67-127)^2=13.47
(130.67-135)^2=18.75
(130.67-128)^2=7.13
(130.67-131)^2=0.11
(130.67-133)^2=5.43
(130.67-127)^2=13.47
total=58.36
n=5
total/n=11.67
***NOTE: This does not include the last number: 1. I am unclear whether 1 here is included or a type.
However, if you include 1 then the standard deviation becomes 48.92.***
For the second set, follow the same pattern.
The answer is 61.62.
I think question itself is confusing. it has been copied twice with some wrong values. I took value which seams to me fitting this question.
values taken 127 135 128 131 133 127 122
Mean value = (127+135+128+131+133+127+122)/7
i.e = 129
Now for variance take difference of each value and mean value
i.e.
-2 , 6, -1, 2, 4, -2, -7
Now sum of Square of these values divided by no. of terms i.e. 7
variance= (4+36+1+4+16+4+49)/7
variance = 16.29
Standard variation is = square root of variance
i.e. Sqroot of 16.29
Answer is 4.035