In: Statistics and Probability
An engineer has designed a valve that will regulate water pressure on an automobile engine. The valve was tested on 150 engines and the mean pressure was 4.6 lbs/square inch. Assume the variance is known to be 1. If the valve was designed to produce a mean pressure of 4.4 lbs/square inch, is there sufficient evidence at the 0.05 level that the valve performs above the specifications? State the null and alternative hypotheses for the above scenario.