In a survey, students are asked how many hours they in a typical week. A five number summary of the responses is 4,5,8,12,20. Which interval describes the number of hours spent studying in a typical week for about 25% of the students sampled?
In: Statistics and Probability
#7. Of 380 randomly selected medical students, 21 said that they planned to work in a rural community. Find a 99% confidence interval for the true proportion of all medical students who plan to work in a rural community.
In: Statistics and Probability
#7. Of 380 randomly selected medical students, 21 said that they planned to work in a rural community. Find a 99% confidence interval for the true proportion of all medical students who plan to work in a rural community.
In: Statistics and Probability
A group of 76 randomly selected students have a mean score of 29.5 with a standard deviation of 5.2 on a placement test. Construct and interpret a 99% confidence interval for the mean score, μ, of all students taking the test.
In: Statistics and Probability
In: Statistics and Probability
A random sample of 320 college students were asked if they believed that places could be haunted and 80 responded yes. Estimate the true proportion of college students who believe in the possibility of haunted places with 99% confidence.
In: Statistics and Probability
In a sample of 41 students, the mean scholarship amount received
was $1138, with a standard deviation of $18.82. Contruct a 90%
confidence interval for the mean scholarship award for all
students. Round your answer to the nearest cent.
________ < μ< _________
In: Statistics and Probability
A random sample of 40 students has a mean annual earnings of $3120.
Assume the population standard deviation, σ, is $677. (Section 6.1)
• Construct a 95% confidence interval for the population mean annual earnings of students.
Margin of error, E._______ Confidence interval: _______ <μ< _______
• If the number of students sampled was reduced to 25 and the level of confidence remained at 95%, what would be the new error margin and confidence interval?
Margin of error, E._______ Confidence interval: _______ <μ< _______
• Did the confidence interval increase or decrease and why?
• If the number of students sampled was increased to 100 and the level of confidence remained at 95%, what would be the new confidence interval?
Margin of error, E._______ Confidence interval: _______ <μ< _______
• Did the confidence interval increase or decrease and why?
In: Math
1. The Graduate Management Admission Test (GMAT) is a test required for admission into many masters of business administration (MBA) programs. Suppose a random sample of 8 students took the test, and their scores are given below. 699, 560, 414, 570, 521, 663, 727, 413
-Find a point estimate of the population mean -Construct and interpret a 95% confidence interval for the true mean score for the population.
-How many students should be surveyed to estimate the mean score within 25 points with 90% confidence?
-How many students should be surveyed to estimate the mean score within 25 points with 95% confidence?
-. How many students should be surveyed to estimate the mean score within 25 points with 99% confidence?
In: Statistics and Probability
A recent survey asked students to rate their stress-level during the first week of classes. Students responded on a scale from 1 to 8 wherein 1 was almost no stress and 8 being stressed to the max. Students responses to the survey are illustrated in the table below.
.
| .. Score . x... | .. Frequency . f .. |
| 1 | 2 |
| 2 | 4 |
| 3 | 7 |
| 4 | 4 |
| 5 | 4 |
| 6 | 1 |
| 7 | 6 |
| 8 | 2 |
.
Using the table information, answer the following:
How many students were surveyed?
What is the mean stress rating? Use 2 decimals in your answer.
What is the median stress rating? Use 2 decimals in your answer.
What is the mode of this data set?
What is the range of this data set?
In: Statistics and Probability