Say I have a sample population A it has mean $\mu_A$. I sample A and obtain another sample population $\hat A$, it has a mean of $\mu_\hat A$.
If a hypothesis test indicates that I should be 95% confident that the two means $\mu_A$ and $\mu_\hat A$ are not equal.
What can I infer about $\hat A$ ?
How might it be different from A.