Suppose you take a 30 question test, multiple choice, with each question having 4 choices. A,...

Suppose you take a 30 question test, multiple choice, with each question having 4 choices. A, B, C, D. If you randomly guess on all 30 questions, what is the probability you pass the exam (correctly guess on 60% or more of the questions)? Assume none of the questions have more than one correct answer. b) what the expected number of correct guesses? what is the standard deviation? c) what would be considered an unusual number of correct guesses on the test?

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orchestra answered 2 years ago

A multiple-choice test has 6 questions. There are 4 choices for each question. A student who...

A multiple-choice test has 6 questions. There are 4 choices for each question. A student who has not studied for the test decides to answer all questions randomly with a Probability of success = p =.25. Let X represent the number of correct answers out of six questions. (i) Use binomial distribution to complete the table (ii) Find the probability that the student will be successful in at least 4 questions. (iii) Find the probability that the student will be...

In a multiple choice exam, there are 7 questions and 4 choices for each question (a,...

In a multiple choice exam, there are 7 questions and 4 choices for each question (a, b, c, d). Nancy has not studied for the exam at all and decides to randomly guess the answers. What is the probability that: (please round all answers to four decimal places) a) the first question she gets right is question number 3? b) she gets all of the questions right? c) she gets at least one question right?

1. On a multiple choice test where each question has 4 choices of which only one...

1. On a multiple choice test where each question has 4 choices of which only one is correct you get 1.8 points for a correct answer and you lose .75 points for an incorrect answer. You lose no points nor gain any points if you leave the problem blank. We let the random variable x = points earned from guessing on a question. a) Find the probability distribution for x b) Is guessing a good idea if you cannot eliminate...

A multiple choice test has 50 questions, with 4 answer choices each. You must get at...

A multiple choice test has 50 questions, with 4 answer choices each. You must get at least 30 correct to pass the test, and the questions are very difficult. a) Are you likely to be able to pass by guessing on every question? Explain. (Hint: use the normal approximation). b) Suppose, after studying for a while, you believe you have raised your chances of getting each question right to 70%. How likely are you to pass now? c) Assuming you...

A multiple choice test consists of 8 items each with 4 choices. A student guesses the...

A multiple choice test consists of 8 items each with 4 choices. A student guesses the answers by choosing an answer at random. Compute the probability that (a) the student answers all questions incorrectly? (b) the student answers all questions correctly? (c) the student answers 2 or more correctly? (d) Suppose the student is able to eliminate one of the answers as incorrect and chooses randomly from the other three choices. What is the probability the student answers 2 or...

2. A student is taking a multiple-choice test in which each question has five choices. Assume...

2. A student is taking a multiple-choice test in which each question has five choices. Assume that the student has no knowledge of the correct answers to any of the questions. She has decided on a strategy in which she will place five balls (marked A, B, C, D and E) into a box. She randomly selected one ball for each question and replaces the ball in the box. The marking on the will determine her answer to the question....

There are 100 multiple-choice question on exam, each having responses a, b, c, d. Suppose that...

There are 100 multiple-choice question on exam, each having responses a, b, c, d. Suppose that a student has a 70% chance to answer each question correctly, and all the answers are independent. If the student needs to answer at least 40 questions to pass, what is the probability that the student passes? Use normal approximation.

An SAT test has 8 questions, each question having 5 multiple choice answers. If a student...

An SAT test has 8 questions, each question having 5 multiple choice answers. If a student make random guesses for each answer, find the probability that: a)the number of correct answers is 7. b)the number of correct answers is at least 4. c)the number of correct answers is fewer than 3.

Suppose that you are taking a multiple choice test (consisting of only 4-answer-choice questions) for which...

Suppose that you are taking a multiple choice test (consisting of only 4-answer-choice questions) for which you have mastered 60% of the material. When you actually take the test, if you know the answer of a question, then you will answer it correctly for sure; if you do not know the answer, however, you can still guess the answer (meaning that you will have 25% chance of getting the correct answer). Finally, assume that your answer to each question is...

1. A student takes a 12 question multiple choice test. There are 5 answer choices, and...

1. A student takes a 12 question multiple choice test. There are 5 answer choices, and the student guesses on all the questions. What is the probability the student will get exactly 7 questions correct in order to pass? Round to 5 decimal places. a. 0.00332 b. 0.00587 c. 0.08304 d. 0.00213 2. If the probability of a machine producing a defective part is 0.05, what is the probability of finding exactly 5 defective parts from a sample of 100?...

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