the average scores of math students in a certain school is 75 with a standard deviation of 8.1. one hundred students were randomly selected, and the average score was found to be 71. the director wants to know wether students have deteriorated. significance level is 0.01

1) the hypotheses are ?

2)Decision and conclusion ?

3) the critical value is ?

4) the test statistic is ?

8. At a university with 1,000 business majors, there are 200 business students enrolled in an introductory Accounting course. Of these 200 students, 50 are also enrolled in an introductory Statistics course. There are an additional 250 business students enrolled in Statistics but not enrolled in Accounting. If a business student is selected at random, what is the probability that the student is either enrolled in Accounting or Statistics or in both courses?

In a class of 130 shs students,41 offers agricultural science ,62 offers business,and 31 offers visual arts .16 of these students offer both agricultural science and business only and 14 offers both business and visual arts only.Assuming none of the students offers all the three subjects ,illustrate the information on a venn diagram

A college professor wants to select three students among twelve students to clean the room. The first student selected will clean the windows, the second student selected will do all the other work, while the third student selected will supervise all activities. In how many different ways can the professor select 3 students form this group.

A university public relations person claims that only 30% of the students were denied enrollment in their preferred major. A student thinks that this proportion is higher. To test the claim of the public relations person a random sample of 10 students was selected. It turned out that 4 of the sampled students could not join their preferred major. Test the claim at the 5% significance level.

The health of college students is monitored by periodically weighing them in. A sample of 32 students has a mean weight of 145.9 lb. Assuming that the population standard deviation is known to be 81.2 lb., use a 0.10 significance level to test the claim that the population mean of all such students weights is different than 150 lb. WHAT ARE THE STEPS ON STATCRUNCH?

Java:

Declare a two-dim array that represents five students with four test scores.

Assign 100 for all tests to all students.

Change the 3rd student’s test 2 to 50.

Change the last student’s last test to 87

Print out all test scores.

Calculate the total points of all tests of all students

6. The Humber Student Federation conducted a survey to determine the mean study time/week of students at the Lakeshore Campus. A sample of 18 students had a mean of 7.5 hours and a standard deviation of 2.2 hours. Assuming that the sampling distribution is about normal, calculate a 99% confidence interval for the mean study time all students at the Lakeshore Campus.

based on a study of 380 dorm residents, the 95% confifence interval for average hours slept per weeknight is from 7.2 to 7.8. That can reasonably be interpreted to mean

- 95% of all students sleep between 7.2 and 7.8 hours per weeknight

-361 (95%) of the 380 students sleep between 7.2 and 7.8 hours per weeknight

-we're 95% sure the average hours slept per weeknight by all students is between 7.2 and 7.8

-we're 95% sure the average hours of sleep per weeknight by the 380 students is between 7.2 and 7.8