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 4 of 5: enter the decision rule. answerhow to enter your answer (opens in new window) 1 point tables keypad keyboard shortcuts reject $h_0$ if $z >$

Explanation:

Step1: Identify the significance level

The significance level $\alpha = 0.02$. Since this is a right - tailed test, we need to find the z - value corresponding to the area of $1-\alpha$ in the standard normal distribution.

Step2: Use the standard normal table

We look up the z - value in the standard normal table (z - table) for an area of $1 - 0.02=0.98$.

Step3: Determine the z - value

From the standard normal table, the z - value corresponding to an area of 0.98 is approximately 2.05.

Answer:

2.05