What are the null hypothesis and the alternative hypothesis?
Should the office building purchase the new brand of florescent bulbs? (i.e. test your hypothesis using a z-test)
This material may consist of step-by-step explanations on how to solve a problem or examples of proper writing, including the use of citations, references, bibliographies, and formatting. This material is made available for the sole purpose of studying and learning - misuse is strictly forbidden.The null hypothesis is that there is no difference between the two brands of bulbs. The alternative hypothesis is that the new brand has a life that is longer than 900 hours. In symbols:
H0: L = 900
Ha: L > 900
L is the average life of the new brand of bulbs.
Since we have more than 30 observations, we can use the z-test. The question is, if we assume that the average lifespan of the new bulbs is 900 with a standard deviation of 80, is the observed average of 920 hours consistent with...