Question

Testing a Claim about a mean (σ unknown)

Suppose the EPA was suing the city of Rochester for non-compliance with carbon monoxide standards. Specifically, the EPA would want to show that the mean level of carbon monoxide levels in downtown Rochester’s air is dangerously high, higher than 4.9 parts per million.

Does a random sample of 22 readings (sample results: xbar=5.25 and s=1.17) present sufficient evidence to support the EPA’s claim? Use α = 0.05.

Answer 1