Problem Set (Hypothesis Testing) 1. A psychologist believes that it will take at leas an hour for certain disturbed children to learn a task. A random sample of 30 of these children results in a mean...

Problem Set (Hypothesis Testing)

1. A psychologist believes that it will take at leas an hour for certain disturbed children to learn a task. A random sample of 30 of these children results in a mean of 50 minutes to learn the task. Should the psychologist modify her belief at the 0.01 level if the population standard deviation can be assumed to be 15 minutes?

2. The mean content of 25 bottles of brand S mango juice is 355 ml with a standard deviation of 9 ml. Is this in line with the manufacturer's claim that the bottle contains, on the average, 360 ml? Use 0.01 level of significance.