HW9_skeleton

9.2

• 1. decreases
• 2. false
• 3. alpha
• 4. true
• 5. true
• 6. Robust
• 1. 1.316

  2. 2.147

  3. 2.552

  4. 1.725

• 1. 2.205

  2. 1.309

  3. 1.943

  4. 2.120

• 13. x bar=21, E=3
• 14. x bar=25, E=5
• 1. (103.656,112.344)

  2. (100.417,115.583)

  3. (104.578,111.422)

  4. No–sample sizes are too small

• 1. Statement is wrong–implies population mean values rather than interval

  2. Statement is correct–interval for population mean is given

  3. Statement is wrong–makes implications about the individuals rather than the mean

  4. Statement is wrong–about mean number adults in US not Idaho

• 29. We are 95% confident that the number of licks to get to the center of a tootsie pop is in between 317.631 and 394.569
• 30. (12.049,14.751)

9.3

• 1. False
• 2. True
• 3. True
• 4. False
• 5. 10.117,30.144
• 6. 12.401,39.364
• 1. 2.81,4.86

  2. 3.48,6.009, the width of the interval decreases as the sample size increases

  3. 2.57,5.6, the width of the interval increases as the confidence level increases

• 11. We are 95% confident that the population standard deviation of the PH of rainwater in Tucker County, West Virginia is between .226 and .542