A nationwide school examination in history included several multiple-choice questions. Each question had 4 possible answers,...
Consider a multiple-choice examination with 50 questions. Each question has four possible answers. Assume that a student who has done the homework and attended lectures has a 65% chance of answering any question correctly. (Round your answers to two decimal places.) (a) A student must answer 43 or more questions correctly to obtain a grade of A. What percentage of the students who have done their homework and attended lectures will obtain a grade of A on this multiple-choice examination?...
Consider a multiple-choice examination with 50 questions. Each question has four possible answers. Assume that a student who has done the homework and attended lectures has a 75% probability of answering any question correctly. A student must answer 43 or more questions correctly to obtain a grade What percentage of the students who have done their homework and attended lectures will obtain a grade A on this multiple-choice examination? A student who answers 35 to 39 questions correctly will receive...
(5 points) A multiple-choice examination has 15 questions, each with 5 possible answers only one of which is correct. Suppose that one of the students who takes the examination answers each of the questions with an independent random guess. What is the probability that the student answers at least four questions correctly? What is the expected number of questions that the student answers correctly? 4. (5 points) A multiple-choice examination has 15 questions, each with 5 possible answers only one...
12. In an entrance examination with multiple choice questions, with each question having four options and a single correct answer, suppose that only 20% candidates think they know the answer to one difficult question and only half of them know it correctly and the other half get it wrong. The remaining candidates pick one option out of the four randomly and tick the same. If a candidate has correctly answered the question, what is the (conditional) probability that she knew...
7. In answering a question on a multiple-choice test, a student either knows the answer or guesses. Let p be the probability that the student knows the answer and 1-p be the probability that the student guesses. Suppose there are 5 multiple-choice alternatives so a student who guesses at the answer will be correct with probability 1/5. (o) Show that the probability that a student knew the answer to a question given that he or she (b) What is the...
3. [10 Points! Consider an exam with multiple choice questions. Assume that each question has three solution choices but only one of them is correct. A student who didn't study for the exam is going to make a guess. 3. What is the probability that he guesses only 15 questions correctly What is the probability that he guesses at least 15 questions correctly c. What is the probability that he guesses more than 10 and less than 15 questions correctly?...
A quiz consists of 6 multiple-choice questions. Each question has 4 possible answers. A student is unprepared, and he has no choice but to guess answers completely at random. He passes the quiz if he gets at least 3 questions correctly. What is the probability that he will pass?
3. [10 Points) Consider an exam with 28 multiple choice questions. Assume that each question has three solution choices but only one of them is correct. A student who didn't study for the exam is going to make a guess. a. What is the probability that he guesses only 15 questions correctly? b. What is the probability that he guesses at least 15 questions correctly? c. What is the probability that he guesses more than 10 and less than 15...
5. A student takes a multiple-choice exam where each question has 5 possible answers. He works a question correctly if he knows the answer, otherwise he guesses at random. Suppose he knows the answer to 80% of the questions. (a) What is the probability that on a question chosen at random the student gets the correct (b) Given that the student gets the correct answer to this question, what is the probability answer? that he actually knew the answer?
A test consists of 25 multiple choice questions. Each question has 5 possible answers, or which only one is correct. If a student guesses on each question, find the following. a) The probability that he will guess all of them correct b)The probability that he will guess at most 15 correct. c)The probability that he will guess at least one correct. d) The mean and the standard deviation of the number of correct answers. e)Estimate the probability of the number...