Form and interpret hypothesis tests for a population mean

An iid random sample has \(n=144\), observed mean \(\overline x=-\frac{9}{4}\) and sample SD \(s=6\). Population σ is unknown. Assume the large-sample normal approximation is adequate

The prespecified hypotheses are H₀: μ=-3 and H₁: μ<-3. Use the approximate z procedure