Question

the national average for the 7th grade aptitude test in 2004 was 85. The principal at...

the national average for the 7th grade aptitude test in 2004 was 85. The principal at O'Farrell Middle School feels that the averagr for his students this year will be different. He randomly selected 10 students to take the aptitude test. Their scores were: 83.4 72.1 89.2 83.3 85.9 79.2 80.3 88.5 90.1

1- state the sample mean and mean and sample standard deviation.

2- Determine 95% confidence interval

3- Does this confidence interval suggest that the average score of 85 is different today than 2004?

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
2. The principal randomly selected six students to take an aptitude test. Their scores (from a...
2. The principal randomly selected six students to take an aptitude test. Their scores (from a normal distribution) were: 83.0 84.1 83.5 83.7 84.1 73.5 a. Determine a 90 percent confidence interval for the mean score for all students.  Show all work.  Identify the standard error, and all calculations of the margin of error. Does it appear as if the mean score was better than 84?  Write the findings as you would in a report (interpret the interval.) b.Assume now that sigma was...
2. Suppose a new standardized test is given to 100 randomly selected third-grade students in New...
2. Suppose a new standardized test is given to 100 randomly selected third-grade students in New Jersey. The sample average score, Y¯ , on the test is 58 points, and the sample standard deviation, sY , is 8 points. (a) Construct a 95% confidence interval for the mean score of all New Jersey third graders. (b) Suppose the same test is given to 200 randomly selected third graders in Iowa, producing a sample average of 62 points and a sample...
A random sample of 36 seventh grade students in Harvard are given a test on a...
A random sample of 36 seventh grade students in Harvard are given a test on a reading test. Below are their raw scores. 73, 77, 80, 80, 84, 86, 91, 93, 93, 93, 94, 97, 100, 100, 103, 103, 104, 105, 105, 106, 108, 110, 111, 117. 120, 120, 123, 124, 126, 128, 129, 129, 130, 130, 136 Sample mean = 105.97 Sample standard deviation = 17.18 Nationally 30% of the students score 110 points or higher on this test....
A dean of a business school is interested in determining whether the mean grade point average...
A dean of a business school is interested in determining whether the mean grade point average (GPA) of students is different from 3.04. The population standard deviation is 0.41. A random sample of 200 students indicates a sample mean GPA of 2.94. A test is conducted at the 0.05 level of significance to determine whether the mean grade point average (GPA) of students is different from 3.04. What is the test statistic value in this test? Select one: a. -0.244...
The National Assessment of Educational Progress (NAEP) includes a mathematical test for eighth-grade students. Scores on...
The National Assessment of Educational Progress (NAEP) includes a mathematical test for eighth-grade students. Scores on the test range from 0 to 500. Suppose that you give the NAEP test to a simple random sample of 900 eighth-graders from a large population in which the scores have mean m = 285 and standard deviation s = 125. The mean will vary if you take repeated samples. 2. (2 points) The sampling distribution of   is approximately Normal. It has mean m =...
In this assignment, you will test for a significant difference between the average resting heart rate...
In this assignment, you will test for a significant difference between the average resting heart rate of males and the average resting heart rate of females in your heart rate data. You have observed that the mean rates are not exactly the same but are they significantly different? You may use either of the two methods for testing a hypothesis illustrated in Realizeit: compare the two confidence intervals or use the data analysis tool to run a two-sample test with...
An IQ test scoring is designed to have mean of 100 and a standard deviation of...
An IQ test scoring is designed to have mean of 100 and a standard deviation of 15. The scores are known to be normally distributed. A principal at a private school wants to investigate whether the average IQ of the students at her school is statistically different from the designed mean. She randomly samples from the school and has 15 students take the IQ test. The average test score of the sample is 95 and the sample standard deviation is...
The Stanford-Binet IQ test has scores that are normally distributed with a mean of 100. A...
The Stanford-Binet IQ test has scores that are normally distributed with a mean of 100. A principal in an elementary school believes that her students have above average intelligence and wants verification of her belief. She randomly selects 20 students and checks the student files. She finds the following IQ scores for these 20 students. IQ scores: 110,132, 98, 97, 115, 145, 77, 130, 114, 128, 89, 101, 92, 85, 112, 79, 139, 102, 103, 89 a. Compute the sample...
Evaluation Title: Assignment 6 Rubric Instructions: In this assignment, you will use the confidence intervals calculated...
Evaluation Title: Assignment 6 Rubric Instructions: In this assignment, you will use the confidence intervals calculated in Unit 5 to determine if two means are the same. Steps: Identify the means and confidence intervals for the resting heart rate for men and women. Use the 95% confidence intervals to determine if the resting male mean is the same as the resting female mean. Repeat the comparison for the 99% confidence interval. Explain why you think the two means are or...
Question 2 *******ONLY NEED F-H******** A.) In order to compare the average heights of children in...
Question 2 *******ONLY NEED F-H******** A.) In order to compare the average heights of children in 5th grade in two different states in US., one takes a random sample of 45 students in state A and a random sample of 65 students in state B. If the two sample means are 62 inches and 55 inches and the two sample standard deviations are 12 and 10, then what would be the standard error of the difference of two sample means?...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT