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 5.0 pounds/square inch. It is believed that the valve performs above the specifications. The valve was tested on 110 engines and the mean pressure was 5.1 pounds/square inch. Assume the variance is known to be 0.49. A level of significance of 0.02 will be used. Find the value of the test statistic. Round your answer to 2 decimal places.

Enter the value of the test statistic.

Answer 1

Solution :

Given that ,

= 5.1

= 5.0

² = 0.49

= 0.7

n = 110

Test statistic = z

= ( - ) / / n

= (5.1 - 5) / 0.7 / 110

= 1.50

Test statistic = 1.50