Homework Answers
(1- α)*100% confidence interval the margin of error=z(α /2)*sd/sqrt(n)
90% confidence interval margin of error=z(0.1/2)*sd/sqrt(n)
or, 1000=1.645*30000/sqrt(n)
or, sqrt(n)=1.645*30000/1000=49.35
n=2435.4 (2436 , next whole number)
answer is 2436
Add Answer to:
A surveyor wants to estimate the average income of daily users of a transit service. The...
A hotel chain wants to estimate the average number of rooms rented daily in each month....
A hotel chain wants to estimate the average number of rooms rented daily in each month. The population of rooms rented daily is assumed to be normally distributed for each month with a standard deviation of 24 rooms During January, a sample of 16 days has a sample mean of 48 rooms. This information is used to calculate an interval estimate for the population mean to be from 40 to 56 rooms. What is the level of confidence of this...
A company wants to test a randomly selected sample of n water specimens and estimate the...
A company wants to test a randomly selected sample of n water specimens and estimate the mean daily rate of pollution produced by a mining operation. If the company wants a 95% confidence interval estimate with a margin of error of 1.7 milligrams per liter (mg/L), how many water specimens are required in the sample? Assume prior knowledge indicates that pollution readings in water samples taken during a day are approximately normally distributed with a standard deviation equal to 7...
in order to estimate the mean amount of time computer users spend on the internet each...
in order to estimate the mean amount of time computer users spend on the internet each month, how many computers users must be surveyed in order to be 95% confidence that your sample mean is within 13 minutes of the population mean? Assume that the standard deviation of the population of monthly time spent on the internet is 218 min. What is a major obstacle to getting a good estimate of the population mean? Use technology to find the estimated...
A researcher with North County Transit wishes to estimate the mean one-way commute distance for students...
A researcher with North County Transit wishes to estimate the mean one-way commute distance for students who attend Palomar College. She wants to construct a 98% confidence interval for the distance to within 2 miles. How large of a sample must she take? Assume that commute distances are normally distributed with a standard deviation of 10.2 miles.
A researcher with North County Transit wishes to estimate the mean one-way commute distance for students...
A researcher with North County Transit wishes to estimate the mean one-way commute distance for students who attend Palomar College. She wants to construct a 98% confidence interval for the distance to within 2 miles. How large of a sample must she take? Assume that commute distances are normally distributed with a standard deviation of 10.2 miles.
An admissions director wants to estimate the mean age of all students enrolled at a college....
An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within 1.7 years of the population mean. Assume the population of ages is normally distributed. (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 1.8 years. (b) The sample mean is 20 years of age. Using the minimum sample size with a 90% level of confidence,...
6. A researcher with North County Transit wishes to estimate the mean one-way commute distance for...
6. A researcher with North County Transit wishes to estimate the mean one-way commute distance for students who attend Palomar College. She wants to construct a 98% confidence interval for the distance to within 2 miles. How large of a sample must she take? Assume that commute distances are normally distributed with a standard deviation of 10.2 miles.
An admissions director wants to estimate the mean age of all students enrolled at a college....
An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within 1.1 years of the population mean. Assume the population of ages is normally distributed (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 1.7 years (b) The sample mean is 21 years of age. Using the minimum sample size with a 90% level of confidence,...
A coal company wants to determine a 95% confidence interval estimate for the average daily tonage...
A coal company wants to determine a 95% confidence interval estimate for the average daily tonage of coal that they mine. Assuming that the company reports that the standard deviation of daily output is 100 tons, how many days should they sample (i.e. find the sample size) so that the margin of error will be 20 tons or less? Please break this down and show me the formula. Thanks
Cholesterol Contents of Cheese A cheese processing company wants to estimate the mean cholesterol content of...
Cholesterol Contents of Cheese A cheese processing company wants to estimate the mean cholesterol content of all one-ounce servings of a type of cheese. The estimate must be within 0.75 milligram of the population mean. (a) Determine the minimum sample size required to construct a 95% confidence interval for the population mean. Assume the population standard deviation is 3.10 milligrams. (b) The sample mean is 29 milligrams. Using the minimum sample size with a 95% level of confidence, does it...
A hotel chain wants to estimate the average number of rooms rented daily in each month. The population of rooms rented daily is assumed to be normally distributed for each month with a standard deviation of 24 rooms During January, a sample of 16 days has a sample mean of 48 rooms. This information is used to calculate an interval estimate for the population mean to be from 40 to 56 rooms. What is the level of confidence of this...
A researcher with North County Transit wishes to estimate the mean one-way commute distance for students who attend Palomar College. She wants to construct a 98% confidence interval for the distance to within 2 miles. How large of a sample must she take? Assume that commute distances are normally distributed with a standard deviation of 10.2 miles.
6. A researcher with North County Transit wishes to estimate the mean one-way commute distance for students who attend Palomar College. She wants to construct a 98% confidence interval for the distance to within 2 miles. How large of a sample must she take? Assume that commute distances are normally distributed with a standard deviation of 10.2 miles.
An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within 1.1 years of the population mean. Assume the population of ages is normally distributed (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 1.7 years (b) The sample mean is 21 years of age. Using the minimum sample size with a 90% level of confidence,...
Most questions answered within 3 hours.
-
Six years of quarterly data of a seasonally adjusted series are
used to estimate a linear...
asked 8 minutes ago -
Which of the following is not an ecological model used
to foster behavior change?
PRECEDE-PROCEED Model...
asked 11 minutes ago -
On the Apollo 14 mission to the moon, astronaut Alan Shepard hit
a golf ball with...
asked 8 minutes ago -
What are John’s potential claims if he is terminated
this week?
John is a 54-year-old man...
asked 21 minutes ago -
A (8.5) cm tall object is placed at a distance of (14.2) cm from
a convex...
asked 30 minutes ago -
(2) For the following questions, consider a data set that
exhibits a normal distribution. Report the...
asked 31 minutes ago -
What exactly is an information system? How does it work" What
are its people organization,
...
asked 32 minutes ago -
The Food Marketing Institute shows that 17% of households spend
more than $100 per week on...
asked 42 minutes ago -
Go to NCBI BLAST search web page
1st search: GEKDLRRAKDINQEVYNF
2nd search: PTSQRLQLLEPFDK
3rd search: GEKDLRRAKDINQEVYNF...
asked 45 minutes ago -
Explain how each of the following three conditions could be a
red flag for a register...
asked 50 minutes ago -
In a two-way factorial ANOVA, the final F-ratio for
factor AxB is determined by dividing _____...
asked 1 hour ago -
Show your solutions for answer.
4. An aqueous solution contains 9.21 g of
K4Fe(CN)6 in a...
asked 50 minutes ago