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No. & Date AskedQuestion
# 893 :: 7/12/11
Question 893 has been Answered
Elbow to fingertip length of men 99% confidence n=32, x- 14.50,s= 0.70 what is the margin of error. . .

Margin of Error, Confidence Intervals

# 868 :: 10/14/10
Question 868 has been Answered
Suppose that a 90% confidence interval for a population mean μ is constructed from a sample, resulting in the interval from 120 to 150. What was. . .

Confidence Intervals, Margin of Error

# 860 :: 3/30/10
Question 860 has been Answered
Problem # 1: Clothing for Runners: Your company sells exercise clothing and equipment on the internet. To design the clothing, you collect a data on. . .

Confidence Intervals, Margin of Error

# 858 :: 3/18/10
Question 858 has been Answered
A questionnaire about study habits was given to a random sample of students taking a large introductory statistics class. The sample of 25 students re. . .

Margin of Error

# 685 :: 4/18/09
Question 685 has been Answered
NKU needs to estimate the mean number of hours that all students work to earn money, on average, per week during the full semesters (fall and spring).. . .

Sample Size, Margin of Error

# 632 :: 2/19/09
Question 632 has been Answered
An automobile manufacturer wants to estimate the mean gasoline mileage that its customers will obtain with its new compact model. How many sample runs. . .

Sample Size, Margin of Error

# 557 :: 12/16/08
Question 557 has been Answered
Find the margin or error for the 95% confidence interval used to estimate the population proportion. In a survey of 7100 TV viewers, 38% said they wa. . .

Confidence Intervals, Margin of Error

# 512 :: 11/14/08
Question 512 has been Answered
When estimating the mean of a population, how large must the sample be in order that the 95% error margin is 1/8 the standard deviation?. . .

Sample Size, Margin of Error, Standard Deviation, Standard Error of the Mean

# 509 :: 11/13/08
Question 509 has been Answered
A researcher expects the population proportion of the Cubs Fans in Chicago to be 80%. Error of less than 5% confident of an estimate to be made from a. . .

Confidence Intervals, Sample Size, Margin of Error

# 508 :: 11/13/08
Question 508 has been Answered
In a national wide survey a researcher expects 30 percent of the population will agree with an value statement. He wishes to have less than 2% error a. . .

Sample Size, Margin of Error, Confidence Level

# 506 :: 11/12/08
Question 506 has been Answered
Suppose you are planning a sample of employees to determine the monthly average # of vacation days. Standards set: Confidence level of 99% and an erro. . .

Sample Size, Margin of Error, Confidence Intervals

# 505 :: 11/11/08
Question 505 has been Answered
Calculate a 98% confidence interval for the following data 15.7,15.7,15.5,15.2,15.2,15.1,15.3.. . .

Confidence Intervals, TINV, Margin of Error, t-statistic

# 504 :: 11/9/08
Question 504 has been Answered
Calculate the 95% confidence interval on the following GPA's from 30 randomly selected students. 0.979 0.891 0.962 0.858 0.909 0.936 0.963 0.9. . .

Confidence Intervals, Margin of Error, t-statistic

# 471 :: 10/9/08
Question 471 has been Answered
A central university has a student population of 60,000. The university is interested in determining what proportion of them is in favour of a new gra. . .

Margin of Error, Confidence Intervals, Sample Size

# 453 :: 10/4/08
Question 453 has been Answered
A central university has a student population of 60,000. The university is interested in determining what proportion of them is in favour of a new gra. . .

Sample Size, Margin of Error

# 450 :: 10/3/08
Question 450 has been Answered
A researcher is interested in estimating the average salary of fire fighters in a large city. He wants to be 95% confident that his estimate is correc. . .

Margin of Error, Sample Size

# 403 :: 9/22/08
Question 403 has been Answered
Based on information obtained from a sample of 54, a 98% confidence interval for the average profit level of regional banks is given by 67.4 million t. . .

Standard Deviation, Margin of Error, Critical Value, Confidence Intervals, Confidence Level

# 371 :: 9/8/08
Question 371 has been Answered
Can you give me a formula to calculate sample size?. . .

Sample Size, Margin of Error

# 369 :: 9/5/08
Question 369 has been Answered
A random sample of 10 miniature Tootsie Rolls was taken from a bag. Each piece was weighed on very accurate scale. The results in grams were 3.087 3.. . .

Margin of Error, Sample Size, Confidence Intervals

# 364 :: 9/4/08
Question 364 has been Answered
A sample of 20 pages was taken without replacement from the 1,591-page phone directory Ameritech Pages Plus Yellow Pages. On each page, the mean area . . .

Margin of Error, Confidence Intervals, Sample Size

# 362 :: 9/1/08
Question 362 has been Answered
Popcorn kernels take between 100 and 200 seconds to pop. What sample size (number of kernels) would be needed to estimate the true mean seconds to pop. . .

Small Sample, Sample Size, Margin of Error, Confidence Intervals

# 339 :: 8/12/08
Question 339 has been Answered
My question is really about sample size. Say you work at a facility and want to perform an assessment of your safety culture – this would involve mul. . .

Sample Size, Margin of Error

# 263 :: 7/6/08
Question 263 has been Answered
Determine the critical value Za/2 that corresponds to 94% level of confidence Compute the 90% confidence interval about m if the sample size, n, is. . .

Critical Value, Confidence Intervals, Margin of Error

# 212 :: 6/1/08
Question 212 has been Answered
How would I figure out a 90% and 95% confidence interval for the below informaion? What would be the formula? Can I figure this out in Excel or Mega. . .

t-distribution, Confidence Intervals, TINV, Margin of Error

# 197 :: 5/15/08
Question 197 has been Answered
Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $30,000 and $45,000. Assum. . .

Normally Distributed, Standard Deviation, Margin of Error, Sample Size

# 151 :: 4/14/08
Question 151 has been Answered
A random sample of 25 households finds that an average of 2.3 people reside in each house (the standard deviation is 0.35). With a 95% confidence lev. . .

TINV, t-statistic, t-distribution, Confidence Intervals, Standard Error of the Mean, Margin of Error

# 6 :: 10/23/07
Question 6 has been Answered
How do you determine the sample size for data for which the mean and standard deviation are not known?. . .

Standard Deviation, Sample Size, Margin of Error