Textbook: Applied Statistics in Business and Economics

Problem 9.27

The target activation force of the buttons on a keyless entry clicker is 1.967 newtons. Variation exists in activation force due to the nature of the manufacturing process. A sample of 9 clickers showed a mean activation force of 1.88 newtons. The standard deviation is known to be 0.145 newton. Too much force makes the keys hard to click, while too little force means the keys might be clicked accidentally. Therefore, the manufacturer's quality control engineers use a two-tailed hypothesis test for samples taken from each production batch, to detect excessive deviations in either direction. At 5 .05, does the sample indicate a significant deviation from the target?

Looking for:

H0:

H1:

Critical Value:

Test Statistic:

Decision:

Conclusion: