A professor gives his students 6 essay questions to prepare for an exam. Only 2 of the questions will actually appear on the exam. How many different exams are possible?
A professor gives his students 6 essay questions to prepare for an exam. Only 2 of...
List the elements of the sample space defined by experiment. 1. a) Roll a single die and then toss a coin c) Toss two coins. 2. Use the counting principle to determine the number of elements in the sample space. Two digits are selected: a) With replacement from the digits 1, 2, 3, and 4 b) Without replacement from the digits 1, 2, 3, and 4. 3. Two-digit natural numbers are formed, with replacement, from the digits 0 through 9.How...
A professor gives a list of 10 problems and tells his students that the exam will consist of 4 of the problems selected at random. If a student knows how to solve 6 of the problems, what is the probability that the student will make a perfect score on the exam? What is the discrete probability distribution used for this problem?
Professor Khan . plans to prepare an exam for his course. Suppose that the exam will contain 15 questions and will be out of 250 points. In how many ways can Professor Khan. assign points to each question so that each question must count for a multiple of 5 points and is worth at least 10 points, but no more than 20 points? BY USING the principle of inclusion and exclusion
An instructor gives an exam with twelve questions. Students are allowed to choose any nine to answer. (a) How many different choices of nine questions are there? (b) Suppose five questions require proof and seven do not. (i) How many groups of nine questions contain three that require proof and six that do not? (ii) How many groups of nine questions contain at least one that requires proof? (iii) How many groups of nine questions contain at most three that...
15. An instructor gives an exam with fourteen questions. Students are allowed to choose any ten to answer. a. How many different choices of ten questions are there? [4 points) b. Suppose the instructions specify that either both questions 1 & 2 are to be included among the ten or neither is to be included. How many different choices of ten questions are there? [4 points)
6. Math instructors are not only interested in how their students do on exams, on average, but how the exam scores vary. To many instructors, the variance, or standard deviation, may be more important than the average. Suppose a math instructor believes that the standard deviation for his final exam is 4.3 points. One of his best students thinks otherwise. The student claims that the standard deviation is more than 4.3 points. The student asks 15 of his classmates for...
A professor has recorded exam grades for 1010 students in his class, but one of the grades is no longer readable. If the mean score on the exam was 8282 and the mean of the 99 readable scores is 8686, what is the value of the unreadable score?
A college professor hands out a list of 12 questions, 6 which will appear on the final examination for the course. One of the students taking the course is pressed for time and can prepare for only 7 of the 12 questions on the list. Suppose the professor chooses 6 questions at random from the 12. What is the probability that the student will be prepared for exactly 4 questions?
Professor Elderman has given the same multiple-choice final exam in his Principles of Microeconomics class for many years. After examining his records from the past 10 years, he finds that the scores have a mean of 76 and a standard deviation of 12. What is the probability that a class of 15 students will have a class average greater than 70 on Professor Elderman’s final exam?
A professor at a university wants to estimate the average number of hours of sleep students get during exam week. On the first day of exams, she asked 27 students how many hours they had slept the night before. The average of the sample was 3.79 with a standard deviation of 1.224. When estimating the average amount of sleep with a 99% confidence interval, what is the margin of error? 1) 0.3549 2) 0.6546 3) 0.5839 4) 0.2356 5) 0.6527