Answer to Question #330230 in Statistics and Probability for eli

Question

Explicate a null hypothesis and its alternative hypothesis in (a) words and in (b) symbols for each of the following. Tell whether the test is directional and non-directional.

1. A librarian of a school claims that all their senior high school students read an average of 10 books a month. A random sample of senior high students read an average 12 books. The confidence statement is 95%.

2. According to a factory employer, the mean working time of workers in the factory is 6. A researcher interviewed 50% of the employees and found out that their mean working time is 8 hours. The 𝛼 level is 0.05.

3. A random sample of 200 students got a mean score of 62 in a knowledge test in mathematics. In the standardization of the test, 𝜇=50.