In a certain factory there are two independent processes manufacturing the same item. The average weight in a sample of 250 items produced from one process is found to be 120 ozs. with a standard deviation of 12 ozs. while the corresponding figures in a sample of 400 items from the other process are 124 and 14. Obtain the standard error of difference between the two sample means. Is this difference significant ? Also find the 99% confidence limits for the difference in the average weights of items produced by the two processes respectively.

In a certain factory there are two independent processes manufacturing the same item. The average weight in a sample of 250 items produced from one process is found to be 120 ozs. with a standard deviation of 12 ozs. while the corresponding figures in a sample of 400 items from the other process are 124 and 14. Obtain the standard error of difference between the two sample means. Is this difference significant ? Also find the 99% confidence limits for the difference in the average weights of items produced by the two processes respectively.

ENGR.ECONOMIC ANALYSIS

14th Edition

ISBN:9780190931919

Author:NEWNAN

Publisher:NEWNAN

Chapter1: Making Economics Decisions

Section: Chapter Questions

Problem 1QTC

See similar textbooks

Similar questions

OA USA Today/CNN/Gallup survey of 365 working parents found 195 who said they spend too little time with their children because of work commitments. a. What is the polnt estimate of the proportion of the population of working parents who feel they spend too little time with their children because of work commitments? (to 4 decimals) b. At 95% confidence, what is the margin of error? (to 4 decimals) c. What is the 05% confidence interval estimate of the population proportion of working parents who feel they spend too little time with their children because of work commitments (to 4 decimals)?
Unbiasedness is a feature of the sample distribution of B1 if a. E ($1) = B₁E[(1/SSTx) Σ diui i=1 n b. E($1) = ß₁E[(1/SSTx) Σ"_¸di + E (µ₁) c.E (61) = - ₁x d. E ($1) = (1/SSTx) + n i=1 Σ¸ i=1 di Hi ○ a. a O b. b ○ c. C ○ d. d
Question 1 The distance between the sample mean and the true population is the sampling error, O True False
Pls solve by using population correction
A major newspaper (that rhymes with Small Street Journal) reported an average household income for its subscribers is $119,155. Assume this estimate of the mean household income is based on a sample of 80 subscribers, and, based on past studies, the population standard deviation is known to be sigma=$30,000. Construct a 95% confidence interval for the population mean. Group of answer choices $60,356 - $177,954 $118,420 - $119,890 $112,447 - $125,863 $112,581 - $125,729
a news paper ad for a manager trainee position contained the statement "our manager trainee have a first year earnings average of $30000 to $40000.Do you think that the ad is describing a confidence interval
Find the confidence interval for estimating the population proportion for parts (a) through (c). a. 90% confidence level; n = 500; p=0.30 b. 95% confidence level; n = 220; p=0.04 c. α = 0.07; n = 345; p=0.50 Click the icon to view the standard normal table of the cumulative distribution function. a. The confidence interval is
Q3
q25- A too wide confidence interval means that Select one: a. estimation is done with high precision b. confidence interval is informative c. estimation is done with a high degree of sampling variability d. the sample size is large Clear my choice
A random sample of 61 lunch customers was selected at a restaurant. The average amount of time the customers in the sample stayed in the restaurant was 35 minutes and the sample standard deviation equals 7.7 minutes. At a 90% level of confidence, what is the margin of error for the confidence interval? a. 1.836 b. 1.647 C. 1.563 d. 1.824 e. 1.833
Solve all questions
All patients admitted to a particular hospital can be released on the same day or kept overnight for observation. In a sample of 2550 patients, 1020 were kept overnight for observation a) What is the point estimate p for the proportion of all patients kept overnight for observation? b) Construct a 99% confidence interval for the proportion of all patients kept overnight for observation.