Assume that 85% of STAT 207 students pass the course. If a random sample of 160...

Assume that 85% of STAT 207 students pass the course. If a random sample of 160 STAT 207 students is taken, find the probability that at least 130 of them pass the course?

Solutions

Expert Solution

P[ STAT 207 students pass the course ] = 85% = 0.85

Number of students = 160

Proportion = 130/160 = 0.8125

The following information has been provided about the population proportion and the sample size:

Population Proportion =	0.85
Sample Size =	160

We need to compute . Based on the information provided, the population men of sample proportions and the corresponding standard error are:

Observe that:

which indicates that the assumption for normal approximation for the sampling distribution is met.

Now, the following is obtained using normal approximation:

= 0.908

P[ umber of students passing more than 130 ] = 0.908

orchestra answered 1 year ago

Next > < Previous

Related Solutions

On January 30th, 2018, Dr. Ziegler took a random sample of STAT 104 students.1 Students were...

On January 30th, 2018, Dr. Ziegler took a random sample of STAT 104 students.1 Students were asked how many Facebook friends they had. Out of 30 respondents who had Facebook accounts, the mean number of friends was 589.10 with a standard error of 72.98. Describe the parameter of interest in context. What is the 95% confidence interval? Interpret the 95% confidence interval. Is 500 friends a plausible value for the population of all STAT 104 students on January 30th, 2018?...

A simple random sample of 70 Stat 20 students is taken from my class of 340...

A simple random sample of 70 Stat 20 students is taken from my class of 340 students; the average number of units these students is taking is 16.1, with an SD of 1.9. Last spring I taught a smaller class with only 96 students, and those 96 students took an average number of units of 15.5, with an SD of 2.2. Do a hypothesis test to decide whether the average number of units for this semester's Stat 20 class is...

As part of a project for their Intro Stat course, two students compared two brands of...

As part of a project for their Intro Stat course, two students compared two brands of chips, Frito Lays and Golden Flakes, to see which company gives you more for your money. Five bags of each brand (which, according to the label, each contained 35.4 grams) were measured with a very accurate scale. Use the Wilcoxon Rank-Sum test to see if there are any significant differences between the two brands in the amount of product they put in their bags....

Assume that a student’s score in a course follows normal distribution. A sample of 10 students’...

Assume that a student’s score in a course follows normal distribution. A sample of 10 students’ scores is as follow: 65, 32, 78, 90, 45, 66, 78, 55, 24, 87. (a) Find the sample mean and sample standard deviation for this sample. (b) Find a 90% confidence interval for the mean score of all the students. Interpret the result. (c) Test, at significance level 10%, if the average score is lower than 70.

USING R : A random sample of 40 students took an SAT preparation course prior to...

USING R : A random sample of 40 students took an SAT preparation course prior to taking the SAT. The sample mean of their quantitative SAT scores was 560 with a s.d. of 95, and the sample mean of their verbal SAT scores was 525 with a s.d. of 100. Suppose the mean scores for all students who took the SAT at that time was 535 for the quantitative and 512 for the verbal. Do the means for students who...

A random sample of 12 second-year university students enrolled in a business statistics course was drawn....

A random sample of 12 second-year university students enrolled in a business statistics course was drawn. At the course's completion, each student was asked how many hours he or she spent doing homework in statistics. The data are listed below. 40, 41, 29, 30, 31, 31, 34, 29, 37, 41, 37, 40 It is known that the population standard deviation is 8. The instructor has recommended that students devote 3 hours per week for the duration of the 12-week semester,...

A random sample of 12 second-year university students enrolled in a business statistics course was drawn....

A random sample of 12 second-year university students enrolled in a business statistics course was drawn. At the course's completion, each student was asked how many hours he or she spent doing homework in statistics. The data are listed below. 281726262620292823271820282626292318172620282720 It is known that the population standard deviation is 9. The instructor has recommended that students devote 2 hours per week for the duration of the 12-week semester, for a total of 24 hours. Test to determine whether there...

A random sample of 12 second-year university students enrolled in a business statistics course was drawn....

A random sample of 12 second-year university students enrolled in a business statistics course was drawn. At the course’s completion, each student was asked how many hours he or she spent doing homework in statistics. The data are listed here. It is know that the population standard deviation is 8. The instructor has recommended that the students devote 36 hours to the course for the semester. Test to determine at the 1% significance level whether there is evidence that the...

A random sample of 12 second-year university students enrolled in a business statistics course was drawn....

A random sample of 12 second-year university students enrolled in a business statistics course was drawn. At the course's completion, each student was asked how many hours he or she spent doing homework in statistics. The data are listed below. 28 18 15 20 14 25 21 29 20 23 24 26 It is known that the population standard deviation is 6. The instructor has recommended that students devote 2 hours per week for the duration of the 12-week semester,...

•Exercise 1: It is assumed that 80% of the students pass the MBA 510 course. Calculate...

•Exercise 1: It is assumed that 80% of the students pass the MBA 510 course. Calculate the following for a class of 15 students: (a) the mean number of students expected to pass; (b) the standard deviation; (c) P(exactly 12 of the 15 students pass); (d) P(at least 12 of the 15 students pass). •Exercise 2: Five customers enter a store and make independent purchase decisions. The store’s records indicate that 20% of all customers who enter the store will...

Subjects