Triola Statistics Test 
Exam
Name___________________________________
Instructions: Read all the questions carefully and show all your work for full credit. All answers must be supported by correct work to receive full credit.
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
Solve the problem.
1) Multiple-choice questions on a test each have 4 possible answers, one of which is correct.
Assume that you guess the answers to 4 such questions.
a. Use the multiplication rule to find the probability that the first two guesses are wrong and the third and fourth guesses are correct. That is, find P(WWCC), where C denotes a correct answer and W denotes a wrong answer.
b. Make a complete list of the different possible arrangements of 2 wrong answers and 2 correct answers, then find the probability for each entry in the list.
c. Based on the preceding results, what is the probability of getting exactly 2 correct answers when 4 guesses are made?
1)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial. Round to three decimal places. 1
2) n = 4, x = 3, p =
2)
6
A) 0.012
3) n = 10, x = 2, p =
A) 0.216
B) 0.004
C) 0.015
D) 0.023
1
3
3)
B) 0.193
C) 0.195
D) 0.003
Find the indicated probability. Round to three decimal places.
4) A test consists of 10 true/false questions. To pass the test a student must answer at least 6 questions correctly. If a student guesses on each question, what is the probability that the student will pass the test?
A) 0.377
B) 0.828
C) 0.172
D) 0.205
4)
5) A 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
Name___________________________________
Instructions: Read all the questions carefully and show all your work for full credit. All answers must be supported by correct work to receive full credit.
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
Solve the problem.
1) Multiple-choice questions on a test each have 4 possible answers, one of which is correct.
Assume that you guess the answers to 4 such questions.
a. Use the multiplication rule to find the probability that the first two guesses are wrong and the third and fourth guesses are correct. That is, find P(WWCC), where C denotes a correct answer and W denotes a wrong answer.
b. Make a complete list of the different possible arrangements of 2 wrong answers and 2 correct answers, then find the probability for each entry in the list.
c. Based on the preceding results, what is the probability of getting exactly 2 correct answers when 4 guesses are made?
1)
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial. Round to three decimal places. 1
2) n = 4, x = 3, p =
2)
6
A) 0.012
3) n = 10, x = 2, p =
A) 0.216
B) 0.004
C) 0.015
D) 0.023
1
3
3)
B) 0.193
C) 0.195
D) 0.003
Find the indicated probability. Round to three decimal places.
4) A test consists of 10 true/false questions. To pass the test a student must answer at least 6 questions correctly. If a student guesses on each question, what is the probability that the student will pass the test?
A) 0.377
B) 0.828
C) 0.172
D) 0.205
4)
5) A 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