On the basis of extensive tests, the yield point of a particular type of mild steel-reinforcing bar is known to be normally distributed with a = 100. The composition of the bar has been slightly modified, but the modification is not believed to have affected either the normality or the value of a. (a) Assuming this to be the case, if a sample of 64 modified bars resulted in a sample average yield point of 8415 lb, compute a 90% CI for the true average yield point of the modified bar. (Round your answers to one decimal place.) ******* Enter a number. (b) How would you modify the interval in part (a) to obtain a confidence level of 92% ? (Round your answer to two decimal places.) ---Select--- e should be changed to You may need to use the appropriate table in the Appendix of Tables to answer this question.
On the basis of extensive tests, the yield point of a particular type of mild steel-reinforcing bar is known to be normally distributed with a = 100. The composition of the bar has been slightly modified, but the modification is not believed to have affected either the normality or the value of a. (a) Assuming this to be the case, if a sample of 64 modified bars resulted in a sample average yield point of 8415 lb, compute a 90% CI for the true average yield point of the modified bar. (Round your answers to one decimal place.) ******* Enter a number. (b) How would you modify the interval in part (a) to obtain a confidence level of 92% ? (Round your answer to two decimal places.) ---Select--- e should be changed to You may need to use the appropriate table in the Appendix of Tables to answer this question.
Glencoe Algebra 1, Student Edition, 9780079039897, 0079039898, 2018
18th Edition
ISBN:9780079039897
Author:Carter
Publisher:Carter
Chapter10: Statistics
Section10.5: Comparing Sets Of Data
Problem 14PPS
Related questions
Question
Transcribed Image Text:On the basis of extensive tests, the yield point of a particular type of mild steel-reinforcing bar is known to be normally distributed with a 100. The composition of the bar
has been slightly modified, but the modification is not believed to have affected either the normality or the value of a.
(a) Assuming this to be the case, if a sample of 64 modified bars resulted in a sample average yield point of 8415 lb, compute a 90% CI for the true average yield
point of the modified bar. (Round your answers to one decimal place.)
Enter a number.
(b) How would you modify the interval in part (a) to obtain a confidence level of 92%? (Round your answer to two decimal places.)
---Select---
should be changed to
You may need to use the appropriate table in the Appendix of Tables to answer this question.
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 4 steps with 10 images
Recommended textbooks for you
Glencoe Algebra 1, Student Edition, 9780079039897…
Algebra
ISBN:
9780079039897
Author:
Carter
Publisher:
McGraw Hill
Glencoe Algebra 1, Student Edition, 9780079039897…
Algebra
ISBN:
9780079039897
Author:
Carter
Publisher:
McGraw Hill