A student wanted to construct a 95% confidence interval for the average age of students in her accounting class. She randomly selected 15 students. The sample mean age was 26.5 years with a sample standard deviation of 2.9 years. What is the 95% confidence interval for the population mean?
A student wanted to construct a 95% confidence interval for the average age of students in...
The average age for all De Anza Students for fall of 2017 is assumed to be normally distributed with a mean of 28.7. The population standard deviation has been pretty consistent at 15. Twenty-five spring 2018 students were randomly selected. The average age for the sample was 26.4. Construct a 95% Confidence Interval for the true average of spring 2018 Evergreen Velley College students.
Confidence Intervals: A group of 50 randomly selected JWU students have a mean age of 20.5 years. Assume the population standard deviation is 1.5 years. Construct a 99% confidence interval for the JWU population mean age. State your answer. (Zc 2.57) 1. 2. Construct a 90% confidence interval for the population mean, . Assume the population has a 2 normal distribution. A random sample of 20 JWU college students has mean annual earnings of 0 $3310 with a standard deviation...
A survey of 25 randomly selected customers found that their average age was 31.84 years with a standard deviation of 9.84 years. What would the critical value t* be for a 95% confidence interval with 99 degrees of freedom? What would the margin of error be for a 95% confidence interval for this data (with the sample size of 25)? Construct a 95% confidence interval for the mean age of all customers for this data (with the sample size of...
What is the average age of students who live off campus? A random sample of 51 students shows the mean of 21.7 years and the standard deviation 2.5 years. Use a 95% level of confidence. a. What is the population parameter to estimate? b. What is the sample statistic? c. Find a 95% confidence interval for population parameter. d. Interpret your interval in the context. e. Melinda assumes that students who live off campus, on average, are older than 25....
1. construct a 95% confidence interval where standard deviation is 15 and mean is 99.133 2. construct a 95% confidence interval where standard deviation is 15 and mean is 99 3. construct a 95% confidence interval where standard deviation is 15 and mean is 98.625 i want to add that the population mean is 100 question 1- sample size is 8 question 2- sample size is 20 question 3- sample size is 30
a.) The margin of error in a 95% confidence interval for the true mean of a population is 2.5, based on a random sample of 100 measurements. If the sample mean is 27.5, the 95% confidence interval must be b.) In a random sample of 100 measurements from a population with known standard deviation 200, the average was found to be 50. A 95% confidence interval for the true mean is c.) A.C. Neilsen reported that children between the ages...
A realtor would like to create a 95% confidence interval for the average price of a house in Franklin County, Ohio. To accomplish this, she collected a random sample of 529 houses and calculated a sample mean price of $320,128. She knows that the population standard deviation for house prices in Franklin County is $50,324. What is her 95% confidence interval?
Determine the minimum sample size needed to construct a 95% confidence interval for the mean age of employees at a company. The estimate must be accurate to within 0.5 year. Assume the standard deviation is 4.8 years?
Suppose we are interested to construct a 95% confidence interval of the mean exam score. A random sample of 36 scores is taken and gives a sample mean (sample mean score) of 68. EBM will be the largest O a when the population standard deviation is 12 points, when the population standard deviation is 18 points. OC when the population standard deviation is 15 points when the population standard deviation is 20 points Od b. Suppose we are interested to...
Use the given degree of confidence and sample data to construct a confidence interval for the population mean y Assume that the population has a normal distribution Thirty randomly selected students took the calculus final the sample mean was 90 and the standard deviation was 5.1. construct a 90% confidence interval for the mean score of all students. Round to be decimal places O A 87.44 <<92.56 OB. 87.71 <<92.29 OC 8743<<92.57 OD 8842 <<91.58