you plan to dive to san antonio from college station to visit your friend lupita. that friend is worried about the drive for you and asks how long it typically takes to make the trip. you kept track of how long it took to drive from 10 previous trips and send her those times. she calculated an average of 2.93 hours and a standard deviation of 0.35 hours from those 10 trips. she decides to calculate a 99% confidence interval. what is the margin of error that lupita calculated?

Russell is doing some research before buying his first house. He is looking at two different areas of the city, and he wants to know if there is a significant difference between the mean prices of homes in the two areas. For the 39 homes he samples in the first area, the mean home price is $⁢176,400. Public records indicate that home prices in the first area have a population standard deviation of $⁢32,930. For the 32 homes he samples in the second area, the mean home price is $⁢181,500. Again, public records show that home prices in the second area have a population standard deviation of $⁢23,835. Let Population 1 be homes in the first area and Population 2 be homes in the second area. Construct a 95% confidence interval for the true difference between the mean home prices in the two areas. Round the endpoints of the interval to the nearest whole number, if necessary. Lowest Endpoint =  upper Endpoint=

Tina catches a 14-pound bass.  She does not know the population mean or standard deviation.  So she takes a sample of five friends and they say the last bass they caught was 9, 12, 13, 10, and 10 pounds.  Find the t and calculate a 95% (α = .05) confidence interval.

Miranda and Karla began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Miranda took a test in Social Studies and earned a 71.4, and Karla took a test in Art History and earned a 60.9. Use the fact that all the students' test grades in the Social Studies class had a mean of 75.3 and a standard deviation of 10.7, and all the students' test grades in Art History had a mean of 66.4 and a standard deviation of 10.3 to answer the following questions.a) Calculate the z-score for Miranda's test grade.z=b) Calculate the z-score for Karla's test grade.z=c) Which person did relatively better? Miranda Karla They did equally well.

Lloyd and Tara began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Lloyd took a test in Social Studies and earned a 77.1, and Tara took a test in Math and earned a 66.4. Use the fact that all the students' test grades in the Social Studies class had a mean of 75.5 and a standard deviation of 10.5, and all the students' test grades in Math had a mean of 65.3 and a standard deviation of 8.8 to answer the following questions.a) Calculate the z-score for Lloyd's test grade.�=b) Calculate the z-score for Tara's test grade.�=c) Which person did relatively better? Lloyd Tara They did equally well.

Logan and Brian began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Logan took a test in Art History and earned a 76.8, and Brian took a test in English and earned a 68.9. Use the fact that all the students' test grades in the Art History class had a mean of 71.9 and a standard deviation of 11.6, and all the students' test grades in English had a mean of 61 and a standard deviation of 9.4 to answer the following questions.a) Calculate the z-score for Logan's test grade.z=z= [Round your answer to two decimal places.] b) Calculate the z-score for Brian's test grade.z=z= [Round your answer to two decimal places.]c) Which person did relatively better? Logan Brian They did equally well.

To celebrate the end of final exams you and friends head to a favorite downtown restaurant. You find a street parking spot with a maximum of two hours. If you stay longer than two hours, you risk having your car towed away. No one has a watch or cellphone but you remember that the average time you spent at the same restaurant over your previous 16 visits is 1.5 hours, and you estimate the sample standard deviation to be about 20 minutes. You also need to factor in that it takes 8 minutes to walk to the restaurant and 8 minutes to walk back to your car (you are very certain about these two durations). (a) One of your friends is really worried that you won’t get back to the car in time and so the car might be towed away! Does your friend have good reason to be worried? Test at a 5% significance level whether the mean total time will be less than two hours. (b) You decide to leave the car parked at the street spot but it gets towed. What type of error have you committed?

Two friends, Karen and Jodi, work different shifts for the same ambulance service. They wonder if the different shifts average different numbers of calls. Looking at past records, Karen determines from a random sample of 40 shifts that she had a mean of 5.1 calls per shift. She knows that the population standard deviation for her shift is 1.2 calls. Jodi calculates from a random sample of 31 shifts that her mean was 5.8 calls per shift. She knows that the population standard deviation for her shift is 1.4 calls. Test the claim that there is a difference between the mean numbers of calls for the two shifts at the 0.01 level of significance. Let Karen's shifts be Population 1 and let Jodi's shifts be Population 2.   Step 3 of 3 :   Draw a conclusion and interpret the decision.