Question

an engineer designed a valve that will regulate water pressure on an automobile engine. the engineer designed the valve such that it would produce a mean pressure of 5.3 pounds/square inch. the valve was tested on 180 engines and the mean pressure was 5.5 pounds/square inch. assume the standard deviation is known to be 1.0. is there evidence at the 0.02 level that the valve performs above the specifications? step 3 of 5: specify if the test is one - tailed or two - tailed. answer 1 point one - tailed test two - tailed test

Explanation:

Step1: Identify the research question

The question is whether the valve performs above the specifications. We are only interested in the upper - tail (if the mean pressure is greater than the specified mean).

Step2: Determine the type of test

Since we are only concerned with the situation where the sample mean is greater than the hypothesized mean (the valve performs above the specifications), it is a one - tailed test.

Answer:

One - Tailed Test