Answer
Variance is 7.33
Standard deviation is 2.71
Work Step by Step
Step 1
First find the mean of the data set which is found by adding up all the numbers and dividing by the number of numbers.
4.2+-3.2+0+1.7+0=2.7
2.7/5=.54
Mean equals .54
Step 2
Variance is found by the equation
$\frac{(s1−M)^2+(s2−M)^2}{N−1}$
Where s is the sample
M is the mean and
N is the number of samples
So the final equation should look like
$\frac{(4.2−.54)^2+(-3.2−.54)^2+(0−.54)^2+(1.7−.54)^2+(0−.54)^2}{5-1}$
Which equals 7.33
7.33 is the variance
Step 3
to find the Standard deviation or Sd
you take the square root of the variance
$\sqrt (7.33)$
Which approximately equals 2.71
The Sd is 2.71