t-test
The \(t\) test is a statistical test for the mean of a population when \(\sigma\) is unknown. It can be used either when \(n\geq30\) or when the population is normally distributed and \(\sigma\) is known.
The formula for the \(t\)-test is:
\[t=\frac{\overline{x}-\mu}{\left(\frac{s}{\sqrt{n}}\right)}\]
The degrees of freedom are \(n-1\)
The assumptions for confidence intervals when \(\sigma\) is unknown need to be met to proceed here as well.