Question

In: Statistics and Probability

5 students attending an exam. Let Si be the event of student i passes an exam....

5 students attending an exam. Let Si be the event of student i passes an exam. S1 and S2 may or may not be independent of each other. Let random variable X be total number of students who pass the exam. P(S1) = P(S2) = 2/3. X = 0, 1, 2, 3, 4, 5.

1) E(X)

2) What is the min and max of var(X)

Solutions

Expert Solution


Related Solutions

Two students attending an exam. Let Si be the event of student i passes an exam....
Two students attending an exam. Let Si be the event of student i passes an exam. S1 and S2 may or may not be independent of each other. Let random variable X be total number of students who pass the exam. P(S1) = P(S2) = 2/3. X = 0, 1, 2. 1) E(X) 2) What is the min and max of var(X)
If a researcher wanted to test whether attending class influences how students perform on an exam,...
If a researcher wanted to test whether attending class influences how students perform on an exam, he collected needed data and decided that the alpha level is 0.05, so the critical value is 3.841 (4 mark) Pass Fail Total attended 25 6 31 skipped 8 15 23 Total 33 21 54 The researcher calculated the expected frequency for each cell and came up with these numbers in parenthesis Pass Fail Total attended 25 (18.94) 6 (12.05) 31 skipped 8 (14.05)...
Consider randomly selecting a student at a large university, and let "A" be the event that...
Consider randomly selecting a student at a large university, and let "A" be the event that the selected student has a Visa card and "B" be the analogous event for MasterCard. Suppose that P(A)=0.6 and P(B)=0.4. a) Could it be the case that P(A and B)=0.5? Why or why not?
Consider randomly selecting a student at a large university, and let A be the event that...
Consider randomly selecting a student at a large university, and let A be the event that the selected student has a Visa card and B be the analogous event for MasterCard. Suppose thatP(A) = 0.7and P(B) = 0.3. (a)Could it be the case thatP(A ∩ B) = 0.5? Why or why not? (b) From now on, suppose thatP(A ∩ B) = 0.2. What is the probability that the selected student has at least one of these two types of cards?...
Consider randomly selecting a student at a large university. Let A be the event that the...
Consider randomly selecting a student at a large university. Let A be the event that the selected student has a Visa card, let B be the analogous event for MasterCard, and let C be the event that the selected student has an American Express card. Suppose that P(A) = 0.6,P(B) = 0.4,and P(A ∩ B) = 0.3,suppose that P(C) = 0.2,P(A ∩ C) = 0.12,P(B ∩ C) = 0.1, and P(A ∩ B ∩ C) = 0.08. a)What is the...
31. An instructor wants to test whether attending class influences how students perform on an exam....
31. An instructor wants to test whether attending class influences how students perform on an exam. There are 54 students in the class. There are 25 students who attended the class and passed the exam, 6 students who attended class and failed the exam, 8 students who skipped the class and passed the exam, 15 students who skipped the class and failed class. Please perform a statistical test and indicate whether attending class influence the exam performance. a) Parametric or...
Let X be the exam grade of a student taking Calculus 1 with Professor Smith. The...
Let X be the exam grade of a student taking Calculus 1 with Professor Smith. The professor believes that X has a mean of 76 and a standard deviation of 12.5. Suppose there are 100 students in Professor Smith's class. Approximate the probability that X is between 73.8 and 77.8.
Let X be the exam grade of a student taking Calculus 1 with Professor Smith. The...
Let X be the exam grade of a student taking Calculus 1 with Professor Smith. The professor believes that X has a mean of 81 and a standard deviation of 22. Suppose there are 100 students in Professor Smith's class. Approximate the probability that X is higher than 83.6 OR smaller than 79.2?
A campus student club distributed material about membership to new students attending an orientation meeting. Of...
A campus student club distributed material about membership to new students attending an orientation meeting. Of those receiving this material, 35​% were men and 65​% were women.​ Subsequently, it was found that 8​% of the men and 11​% of the women who received this material joined the club. Complete parts a and b below. a. Find the probability that a randomly chosen new student who receives the membership material will join the club. nothing ​(Round to four decimal places as​...
At a recent transfer student event held at MPC, students were asked their major field of...
At a recent transfer student event held at MPC, students were asked their major field of study. A sample of the responses collected follow: English, Engineering, Psychology, English, Computer Science, Engineering, Computer Science, Psychology, Engineering, Engineering Math, Biology, Biology, Engineering, Sociology Math, English, Biology, Engineering, Engineering a. Construct a Frequency Distribution Table for this Qualitative Data. Include a column for relative frequency. b. Draw a pareto graph for this data.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT