Homework 17

Problems

Section 9.1:

• 1
• 2
• 3

Section 9.2:

Instructions:

1. You should test all hypotheses using the confidence interval-based method we developed in class. For this homework, do not use the test statistic-based method presented in Chapter 9.
   • Reminder: "significance level" or "level" of a test is a synonym for \(\alpha\).
2. You should sketch all confidence intervals, and include the null parameter value in your sketch.
3. Be careful to distinguish between when you should uze a \(z\)-based or \(t\)-based interval.
4. Be careful to distinguish between when you should use a confidence interval, upper confidence bound, or lower confidence bound to test the hypothesis.

• 17a
• 18ab
• 19a
• 20
  • Note that in the table "Mean" is the sample mean of the 50 lightbulb lifetimes, and "StDev" is their sample standard deviation.
• 22
• 23