Suppose you want to estimate the mean number of fries that are sold at McDonald's between 11am and noon every day. For 100 days, you found a sample mean of 30 and a sample standard unbiased deviation of 15. Provide a 95% confidence interval for the mean number of fries you wanted to estimate.
Given : Sample size=100
Sample mean=
Sample standard deviation=s=15
Significance level=
Now ,
; From t-table
Therefore , the 95% confidence interval for the mean number of fries you wanted to estimate is ,




Suppose you want to estimate the mean number of fries that are sold at McDonald's between...
A gasoline station owner wanted to estimate the mean number of gallons sold per customer. He selected a random sample of 60 customers and found a mean of 8.6, with a Standard Deviation of 2.3. What would be the 95% Confidence Interval for his sampling? 8.6 +/- 1.96 (2.3/sq rt 60) = 8.6 +/- 1.96 (2.3/7.75) = 8.6 +/- 0.58 = 8.02 to 9.18 So there is a 95% probability that the true mean of gallons purchased would be between...
Suppose there is a McDonald's next to your school and you want to estimate the proportion, p of all people at your school who go to McDonald's on a typical school day. (a) If you had no preliminary estimate for p. how many people should you include in a random sample to be 85% sure that the estimate will be within a distance of 0.05 from p? Make sure to show the formula with the numbers plugged in. (b) Complete...
Suppose there is a McDonald's next to your school and you want to estimate the proportion, p of all people at your school who go to McDonald's on a typical school day. (a) If you had no preliminary estimate for p. how many people should you include in a random sample to be 85% sure that the estimate will be within a distance of 0.05 from p? Make sure to show the formula with the numbers plugged in. (b) Complete...
Assume that you want to construct a 95% confidence interval estimate of a population mean. Find an estimate of the sample size needed to obtain the specified margin of error for the 95% confidence interval. The sample standard deviation is given below. Margin of error =$5,standard deviation=$25 The required sample size is ????? (Round up to the nearest whole number as needed.)
Assume that you want to construct a 95% confidence interval estimate of a population mean. Find an estimate of the sample size needed to obtain the specified margin of error for the 95% confidence interval. The sample standard deviation is given below. Margin of error equals=$66, standard deviation equals=$2222 The required sample size is _____. (Round up to the nearest whole number as needed.)
QUESTION7 4 days. On the basis of the study conducted last suppose you want to estimate with 95% confidence interval, the population mean processing time to within year, you believe the standard deviation is 25 days. Determine the minimum sample size rer.ba.^^ìh-. n.eeet, т.c , nrpenr Ai T4FN.FlorMan
Assume that you want to construct a 95% confidence interval estimate of a population mean. Find an estimate of the sample size needed to obtain the specified margin of error for the 95% confidence interval. The sample standard deviation is given below. Margin of errorequals $3, standard deviationequals $23 The required sample size is nothing . (Round up to the nearest whole number as needed.)
Assume that you want to construct a 95% confidence interval estimate of a population mean. Find an estimate of the sample size needed to obtain the specified margin of error for the 95% confidence interval. The sample standard deviation is given below. Margin of error equals$5, standard deviation equals$19 The required sample size is __.
Suppose you work for the Department of Natural Resources and you want to estimate, with 95% confidence, the mean length of recently hatched fish in a fish hatchery pond. You take a random sample of 10 fish and determine that the sample mean length is 7.5 inches and the sample standard deviation is 0.83 inches. (Assume that fish length is normally distributed in this population.) (a) Construct a 95% confidence interval for the mean length of recently hatched fish at...
You want to estimate the mean IQ for a population of students with a 95% confidence interval. Assume that the population standard deviation is known to be 15. If you want your estimate to be within 5 points of the value of the parameter, you will need a sample size of... (Round z to the nearest hundredth.)