Answer :
The standard error on the mean of these numbers is 1.08
For given question,
suppose your group measures the following three numbers in some experiment: 12.4,7.8,10.2
Mean of these numbers is:
[tex]\bar x=\frac{ 12.4+7.8+10.2}{3}\\\\ \bar x=10.13[/tex]
So the standard deviation would be,
[tex]\sigma=\sqrt{\frac{(12.4-10.13)^2+(7.8-10.13)^2+(10.2-10.13)^2}{3} }\\\\\sigma=1.88[/tex]
Now we find the standard error on the mean of these numbers.
[tex]\sigma_M=\frac{\sigma}{\sqrt{N} }[/tex]
where, [tex]\sigma_M[/tex] = standard error of the mean
σ = the standard deviation of the original distribution
N = the sample size
[tex]\sigma_M=\frac{1.88}{\sqrt{3} }\\\\\sigma_M=1.08[/tex]
Therefore, the standard error on the mean of these numbers is 1.08
Learn more about the standard error on the mean here:
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