In a certain college, 33 of the physics majors belong to ethnic minorities. If 10 students are selected at random from the physics majors, what is the probability that no more than 6 belong to an ethnic minority?
A) 0.0547 B) 0.9815 C) 0.9846 D) 0.9130
Q. 2The policy committee at State University has 6 members: LaToyna, Ming, Jose, John, Prof. Rise, and Dr. Hernandez. A subcommittee of two members must be formed to investigate the visitation policy in the dormitories.
List all possible simple random samples of size 2.
A) LaToyna and Ming, Ming and Jose, Jose and John, John and Prof. Rise, Prof. Rise and Dr. Hernandez
B) LaToyna and Ming, LaToyna and Jose, LaToyna and John, LaToyna and Prof. Rise, LaToyna and Dr. Hernandez, Ming and Jose, Ming and John, Ming and Prof. Rise, Ming and Dr. Hernandez, Jose and John, Jose and Prof. Rise, Jose and Dr. Hernandez, John and Prof. Rise, John and Dr. Hernandez, Prof. Rise and Dr. Hernandez
C) LaToyna and Ming, LaToyna and Jose, LaToyna and John, LaToyna and Prof. Rise, LaToyna and Dr. Hernandez
D) LaToyna and Ming, Jose and John, Prof. Rise and Dr. Hernandez
Q. 3A quiz consists of 50 multiple choice questions, each with five possible answers, only one of which is correct. Find the mean and the standard deviation of the number of correct answers.
A) mean: 10; standard deviation: 3.16227766 B) mean: 10; standard deviation: 2.82842712
C) mean: 25; standard deviation: 5 D) mean: 25; standard deviation: 2.82842712
Q. 4A recent study attempted to estimate the proportion of Florida residents who were willing to spend more tax dollars on protecting the Florida beaches from environmental disasters. Forty-five hundred Florida residents were surveyed.
Which of the following is the population used in the study?
A) the 4500 Florida residents surveyed
B) all Florida residents who lived along the beaches
C) all Florida residents
D) the Florida residents who were willing to spend more tax dollars on protecting the beaches from environmental disasters
Q. 5A machine has 12 identical components which function independently. The probability that a component will fail is 0.2. The machine will stop working if more than three components fail. Find the probability that the machine will be working.
A) 0.7946 B) 0.2362 C) 0.2054 D) 0.7638
Q. 6n = 132, x = 87; 90 level
A) 0.590 to 0.728 B) 0.593 to 0.725 C) 0.595 to 0.723 D) 0.591 to 0.727
Q. 7A quiz consists of 620 true or false questions. If the student guesses on each question, what is the standard deviation of the number of correct answers?
A) 0 B) 17.6068169 C) 2 D) 12.4498996
Q. 8The city council of a small town needs to determine if the town's residents will support the building of a new library. The council decides to conduct a survey of a sample of the town's residents.
Which one of the following procedures would be most appropriate for obtaining a sample of the town's residents?
A) Survey every 7th person who enters the old library on a given day.
B) Survey a random sample of persons within each neighborhood of the town.
C) Survey a random sample of librarians who live in the town.
D) Survey 400 individuals who are randomly selected from a list of all people living in the state in which the town is located.
Q. 9A researcher wishes to estimate the proportion of all drivers who exceed the speed limit on a certain stretch of road where accidents frequently happen.
Obtain a sample size that will ensure a margin of error of at most 0.022 for a 92 confidence interval.
A) 20 B) 904 C) 35 D) 1582