The average waiting time of 64 r/s Bank A’s customers at its branches is 4.87 minutes with s.d. 1.10 minutes. An independent random sample of 100 Bank B customers yields an average waiting time of 4.50 minutes with s.d. 1.21 minutes. Construct a 95% c.i. for the difference between the overall average waiting times of the two banks’ customers

The average waiting time of 64 r/s Bank A’s customers at its branches is 4.87 minutes with s.d. 1.10 minutes. An independent random sample of 100 Bank B customers yields an average waiting time of 4.50 minutes with s.d. 1.21 minutes. Construct a 95% c.i. for the difference between the overall average waiting times of the two banks’ customers

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The amount of chlorine in 100 cm3 water taken from a water tank was measured, the average was 2.15 mg was found. The expert claims that the amount of chlorine in the water is greater than that measured. For this reason, 100 households were randomly selected, with an average chlorine content of 2.55mg and a variance of 0.49 mg. According to this data, find the account value z. 13 - O A) 8,15 O B) 5,71 O C) -5,71 O D) -8, 15 O E) 0.54
A psychology graduate student wants to test the claim that there is a significant difference between the IQs of spouses. To test this claim, she measures the IQs of 9 married couples using a standard IQ test. The results of the IQ tests are listed in the following table. Using a 0.10 level of significance, test the claim that there is a significant difference between the IQs assuming that the population distribution of the paired differences is approximately normal. Let the spouse 1 group be Population 1 and let the spouse 2 group be Population 2. Spouse 1 Spouse 2 IQs of Married Couples 124 113 97 123 121 101 128 116 96 126 119 100 Copy Data Step 2 of 3: Compute the value of the test statistic. Round your answer to three decimal places. 124 111 127 113 107 111
The data is presented in parallel format. Before running the ANOVA in Excel, you will need to put it into serial (column) format. You will need to create a categorical variable for the first factor (days) and for the second factor (time of day). This is a critical step.The data presented shows exam scores for students randomly assigned to the sections meeting on these days at these times of the day: Thursday Friday Morning Afternoon Morning Afternoon 70.878.15978.246.646.476.559.376.370 65.678.359.359.778.680.892.780.865.392.3 90.890.569.177.36977.558.677.877.558.6 63.372.854.254.472.166.26372.56672.2 Conduct a 2-way ANOVA. First, find the group means for each level of the factors. (Report answers accurate to 2 decimal places.)Days: MThursday=MThursday= MFriday=MFriday= Time of day: Mmorning=Mmorning= Mafternoon=Mafternoon= Report the results of the ANOVA for the main & interaction effects. (Report P-values accurate to 4 decimal places and…
Water samples are taken from water used for cooling as it is being discharged from a power plant into a river. It has been determined that as long as the mean temperature of the discharged water is at most 150°F, there will be no negative effects on the river's ecosystem. To investigate whether the plant is in compliance with regulations that prohibit a mean discharge water temperature above 150°, 50 water samples will be taken at randomly selected times and the temperature of each sample recorded. The resulting data will be used to test the hypotheses Ho: μ = 150° versus H₂: μ > 150°. In the context of this situation, describe type I error. a A type I error occurs when our estimate for the mean discharge temperature is higher than the actual temperature. A type I error occurs when we say that the plant is not in compliance when in fact it is. A type I error occurs when our estimate for the mean discharge temperature is lower than the actual temperature. A type I error occurs when we…
The heights of men in a certain city are normally distributed with a mean of 275 cm and a variance of 25cm. Compute the minimum height for the top sixteen percent of the men in the city.
Assume that a high school principal believes that high number of absences hinders the students' ability to perform on standardized tests. He randomly selects a sample of 9 students who had 5 or more absences in the school year. The average ACT Composite score for this sample is X = 19 with s = 4.9. ACT Composite scores are normally distributed with u = 21.0. Do the data support the claim that the high number of absences hinders the students' ability to perform on standardized tests, using a = .05? Please show the four-step hypothesis test. %3D
A survey of the population of 51 students in Psych 311 asks how many credits students are taking and obtains the following normally-distributed results: ∑ X= 686 and ∑X2= 9832.92. Using this information, answer the following three questions. What is the percentile rank of a student who is enrolled in 15 credits? (Hint: This is the same thing as asking “what percentage of students is enrolled in 15 credits or less?”) MUST SHOW WORK FOR THIS PROBLEM What percentage of students are enrolled in between 12 and 18 credits? (MUST SHOW WORK FOR THIS PROBLEM) What is the 25th percentile? (Hint: This is the same as asking what score separates the bottom 25% of the distribution from the top 75%.) MUST SHOW WORK FOR THIS PROBLEM
A researcher predicts that smoking cigarettes decreases a person's sense of smell. On a test of olfactory sensitivity (smell), the mean for non-smokers is 18.4. A sample of 12 people who smoke a pack each day have a sample mean of 16.25 (sample variance = 4.75). Complete the following statement: We ["", ""] the null. Smokers have ["", "", ""] in olfactory sensitivity compared to non-smokers.
In a summary report given by Ing. Pobbi on the lengths of ironrods produced by two machines, he stated that the variability ofmachine A was higher compared to that of machine B. Critiquethe report of the Engineer given data on the length of rodsproduced given as; MachineA(cm): 380 410 280 310 305 360 270 355 400 Machine B(m): 1.1 1.3 1.2 2.0 1.5 1.6 1.4 1.6 1.7
A researcher collected data from a sample of correctional officers and found that, on average, they made 47,173 dollars a year with S=6,364. Assuming that their salaries were normally distributed what proportion of correctional officers make less than 40,000 dollars a year?
Gary has discovered a new painting tool to help him in his work. If he can prove to himself that the painting tool reduces the amount of time it takes to paint a room, he has decided to invest in a tool for each of his helpers as well. From records of recent painting jobs that he completed before he got the new tool, Gary collected data for a random sample of 7 medium-sized rooms. He determined that the mean amount of time that it took him to paint each room was 3.4 hours with a standard deviation of 0.3 hours. For a random sample of 6 medium-sized rooms that he painted using the new tool, he found that it took him a mean of 3.2 hours to paint each room with a standard deviation of 0.2 hours. At the 0.05 level, can Gary conclude that his mean time for painting a medium-sized room without using the tool was greater than his mean time when using the tool? Assume that both populations are approximately normal and that the population variances are equal. Let painting times without using…
Compute the test statistic