Your statistics instructor wants you to determine a confidence interval estimate for the mean test score. Past experience indicated that tests scores are normally distributed with a sample mean of 160 and a population standard deviation of 45. The critical value to estimate a 95% confidence interval of the population means is A. 1.645 B. 1.96

Your statistics instructor wants you to determine a confidence interval estimate for the mean test score. Past experience indicated that tests scores are normally distributed with a sample mean of 160 and a population standard deviation of 45. The critical value to estimate a 95% confidence interval of the population means is A. 1.645 B. 1.96

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

See similar textbooks

Similar questions

You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately 38.3. You would like to be 98% confident that your estimate is within 1 of the true population mean. How large of a sample size is required?
HELP I NEED IN ONE HOUR.
how do i solve parts A-F?
One year, the mean age of an inmate on death row was 38.3 years. A sociologist wondered whether the mean age of a death-row inmate has changed since then. She randomly selects 32 death-row inmates and finds that their mean age is 37.3, with a standard deviation of 8.7. Construct a 95% confidence interval about the mean age. What does the interval imply? E Click the icon to view the table of critical t-values. Choose the correct hypotheses. H, Hi: (Type integers or decimals. Do not round.) Construct a 95% confidence interval about the mean age. With 95% confidence, the mean age of a death row inmate is between places as needed.) What does the interval imply?
You measure 49 dogs' weights, and find they have a mean weight of 72 ounces. Assume the population standard deviation is 13.1 ounces. Based on this, construct a 90% confidence interval for the true population mean dog weight. Give your answers as decimals, to two places
A group of 70 Western Grey Squirrels were studied in Los Angeles . The sample mean of these squirrels was found to be 1.73 pounds. Based on previous studies we can assume that the standard deviation of this squirrel population, o, is 0.13. 1. Find a 90% confidence interval for the average weight of Western Grey Squirrels in the study region. (Round to three decimal places) ter 2. Interpret your result. Make sure to answer both questions. Write down what test you used from your calculator and the values you entered.
SAT scores are distributed with a mean of 1,500 and a standard deviation of 300. You are interested in estimating the average SAT score of first year students at your college. If you would like to limit the margin of error of your 95% confidence interval to 25 points, how many students should you sample? Round answer to nearest whole number.
One year, the mean age of an inmate on death row was 40.1 years. A sociologist wondered whether the mean age of a death-row inmate has changed since then. She randomly selects 32 death-row inmates and finds that their mean age is 39.3, with a standard deviation of 9.9. Construct a 95% confidence interval about the mean age. What does the interval imply? Click the icon to view the table of critical t-values. C Choose the correct hypotheses. Ho: ▼ H₁₂: (Type integers or decimals. Do not round.) Construct a 95% confidence interval about the mean age. years and years. (Round to two decimal places as needed.) With 95% confidence, the mean age of a death row inmate is between What does the interval imply? O A. Since the mean age from the earlier year is not contained in the interval, there is not sufficient evidence to conclude that the mean age had changed. O B. Since the mean age from the earlier year is contained in the interval, there is sufficient evidence to conclude that the mean age…
You measure 43 dogs' weights, and find they have a mean weight of 34 ounces. Assume the population standard deviation is 13.8 ounces. Based on this, construct a 95% confidence interval for the true population mean dog weight.Give your answers as decimals, to two places
The dean randomly selected 33 students who took the calculus final exam and looked at their scores on it. In this sample the mean was 80.3 and the standard deviation was 3.7. No information about the population's distribution is available. Construct a 98% confidence interval for the mean score of all students who took this exam. Round your answers to 2 places after the decimal point, if necessary. If it is not appropriate to construct a confidence interval in this situation, then enter "0" in both answer boxes below. 98% confidence interval:
You measure 43 dogs' weights, and find they have a mean weight of 34 ounces. Assume the population standard deviation is 13.8 ounces. Based on this, construct a 95% confidence interval for the true population mean dog weight.Give your answers as decimals, to two places
Choose the appropriate statistical test. When computing, be sure to round each answer as indicated. A dentist wonders if depression affects ratings of tooth pain. In the general population, using a scale of 1-10 with higher values indicating more pain, the average pain rating for patients with toothaches is 6.8. A sample of 30 patients that show high levels of depression have an average pain rating of 7.1 (variance 0.8). What should the dentist determine? 1. Calculate the estimated standard error. (round to 3 decimals). [st.error] 2. What is thet-obtained? (round to 3 decimals). 3. What is the t-cv? (exact value) 4. What is your conclusion? Only type "Reject" or Retain"