Chapter 9 for students

Chapter 9 for students - Chapter 09 - Estimation and...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 09 - Estimation and Confidence Intervals Chapter 9 Estimation and Confidence Intervals 1. 51.314 and 58.686, found by 2. 38.911 and 41.089, found by 3. a. 1.581, found by b. The population is normally distributed and the population variance is known. c. 16.901 and 23.099, found by 20 ± 3.099 4. 1.44 5. a. $20. It is our best estimate of the population mean. b. $18.60 and $21.40, found by about 95 percent of the intervals similarly constructed will include the population mean. 6. a. $18.775 and $21.225, found by b. The confidence interval is based on the standard error computed by . As n , the sample size, increases (in this case from 49 to 64) the standard error decreases and the confidence interval becomes smaller. 7. a. 8.60 gallons b. 7.83 and 9.37, found by c. If 100 such intervals were determined, the population mean would be included in about 99 intervals. 9-1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Chapter 09 - Estimation and Confidence Intervals 8. 5.29 and 6.81 errors found by 9. a. 2.201 b. 1.729 c. 3.499 10. a. 2.145 b. 2.500 c. 1.796 11. a. The population mean is unknown, but the best estimate is 20, the sample mean. b. Use the t distribution as the standard deviation is unknown. However, assume the population is normally distributed. c. 2.093 d. Between 19.06 and 20.94, found by . e. Neither value is reasonable because they are not inside the interval. Chapter 9 2
Background image of page 2
Chapter 09 - Estimation and Confidence Intervals 12. a. The population mean is unknown, but the best estimate is 60, the sample mean. b. Use the t distribution as the standard deviation is unknown and the sample size is small. However, assume the population is normally distributed. c.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/30/2010 for the course BUSS 202 taught by Professor Ritageutchian during the Three '10 term at Notre Dame AU.

Page1 / 13

Chapter 9 for students - Chapter 09 - Estimation and...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online