Selecting, Implementing, and Communicating Inference Procedures Practice Test

An environmental agency wants to test whether the mean nitrate concentration in a river exceeds 10 mg/L. Technicians collect a random sample of 25 water samples from different locations along the river on the same day and measure nitrate concentration (mg/L) for each sample. Which inference procedure is most appropriate for this hypothesis test about the population mean concentration?

A city wants to estimate the proportion of households that support a proposed recycling fee. A simple random sample of 500 households is contacted, and each household responds either “support” or “do not support.” The parameter of interest is the population proportion who support the fee. Which inference procedure is most appropriate?