A company has developed a new ink-jet cartridge for its printer that it believes has a longer life-time on average than the one currently being produced. To investigate its length of life, 225 of the new cartridges were tested by counting the number of high-quality printed pages each was able to produce. The sample mean was determined to be 1511.4 pages. The population standard deviation is known to be 35.7 pages. The historical average lifetime for cartridges produced by the current process is 1502.5 pages.
-What is the rejection point for α = .05 to test the hypotheses?
A)1.645
B)-1.645
C)1.96
D)1.28
E)-1.96

Question

Quizplus · Accepted Answer

The rejection point for a one-tailed test at α = 0.05 is 1.645 when using a standard normal distribution (Z-distribution).

A Company Has Developed a New Ink-Jet Cartridge for Its