4. One hundred students were interviewed. Forty–two are Monthly Active Users (MAU) of Facebook (F), and...

4. One hundred students were interviewed. Forty–two are Monthly Active Users (MAU) of Facebook (F), and sixty–five are MAU of Snapchat(S). Thirty–four are MAU of both Facebook and Snapchat. One of the100 students is randomly selected, all 100 students having the same probability of selection (1/100).

(a) What is the probability that the student is an MAU of Facebook?

(b) What is the probability that the student is an MAU of Facebook given that the student is an MAU of Snapchat?

d) Express the probability in Part (b) in symbols, that is in a similar fashion to Part (c).

5. The students in Question 4 were also asked if they were MAU of Twitter. Twenty five were MAU of Twitter, including 15 who were MAU of Facebook and Twitter and 16 who were MAU of Twitter and Snapchat. Twenty four students were not MAU of any of Facebook, Snapchat or Twitter.

(a) What is the probability that a randomly selected student is an MAU of Facebook, Snapchat, and Twitter?

(b) What is the probability that a randomly selected student is an MAU of Twitter, conditional on that student being an MAU of both Facebook and Snapchat?

Solutions

Expert Solution

milcah answered 9 months ago

Next > < Previous

Related Solutions

One hundred students were placed into two groups. The two groups were the South Beach diet...

One hundred students were placed into two groups. The two groups were the South Beach diet and Keto diet. Below are the data for pounds lost after 1 month of dieting. Assume the data are normal and that the sample size is 100 (but, use the values you have). Tell me if there is a difference between the two diets. Show all of your work. SB Keto 2.5 3.5 3.2 3.7 3.0 4.0 5 4.1 2.3 4.0 2.7 2.5 1.0...

Facebook recently examined all active Facebook users and determined that the average user has 183 Facebook...

Facebook recently examined all active Facebook users and determined that the average user has 183 Facebook friends. Suppose that the population of number of Facebook friends of a randomly selected user has a standard deviation of σ = 241. Facebook draws a SRS of 250 Facebook users. What is the probability that the average number of Facebook friends is less than 175? Apply the Central Limit Theorem. Caution: do not round at your intermediate steps. Hint: you may need to...

One hundred randomly selected subjects from 51,048 subjects were interviewed as a part of the California...

One hundred randomly selected subjects from 51,048 subjects were interviewed as a part of the California Health Interview Survey. The table below was constructed from the responses of the 100 subjects. Use a 0.05 significance level to test the claim that for California adults, exercise is independent of gender. Have you exercised vigorously in the last 7 days? YES NO MALE 13 34 FEMALE 15 38

2. Two hundred managers from various levels were randomly selected and interviewed regarding their concern about...

2. Two hundred managers from various levels were randomly selected and interviewed regarding their concern about environmental issues. The response of each person was tallied into one of the three categories: No concern, some concern and great concern. The results were: Level of Management No Concern Some concern Great concern Top Management 15 13 12 Middle Management 20 19 21 Supervisor 776 Group Leader 28 21 31 Use the .01 significance level to determine whether there is a relationship between...

2. Two hundred managers from various levels were randomly selected and interviewed regarding their concern about...

2. Two hundred managers from various levels were randomly selected and interviewed regarding their concern about environmental issues. The response of each person was tallied into one of the three categories: No concern, some concern and great concern. The results were: Level of Management No Concern Some concern Great concern Top Management 15 13 12 Middle Management 20 19 21 Supervisor 7 7 6 Group Leader 28 21 31 Use the .01 significance level to determine whether there is a...

One hundred students were given an Algebra test. A random sample of ten students was taken...

One hundred students were given an Algebra test. A random sample of ten students was taken out of class of 800 enrolled students. The time it took each student to complete the test is recorded below. 22.2, 23.7, 16.8, 18.3, 19.7, 16.9, 17.2, 18.5, 21.0, and 19.7 a. Find the mean, variance and standard deviation for this sample of ten students b. Construct a 95% confidence interval for the population mean time to complete this Algebra test. c. Test if...

An exhaustive study of all active Facebook accounts was recently conducted by Facebook. One variable Facebook...

An exhaustive study of all active Facebook accounts was recently conducted by Facebook. One variable Facebook recorded was the number of friends X of each Facebook user. Suppose X has expected value E(X) = 180 and standard deviation SD(X) = 280.7. Since the possible values of X are only integers and since the distribution of X is highly skewed to the right, the distribution of X cannot be described by a normal model. Suppose you select a random sample of...

An exhaustive study of all active Facebook accounts was recently conducted by Facebook. One variable Facebook...

An exhaustive study of all active Facebook accounts was recently conducted by Facebook. One variable Facebook recorded was the number of friends X of each Facebook user. Suppose X has expected value E(X) = 187 and standard deviation SD(X) = 283.6. Since the possible values of X are only integers and since the distribution of X is highly skewed to the right, the distribution of X cannot be described by a normal model. Suppose you select a random sample of...

Nine hundred forty-seven cubic feet of wet air at 70 F and 29.2 in. Hg are...

Nine hundred forty-seven cubic feet of wet air at 70 F and 29.2 in. Hg are dehydrated. If 0.94 lbs of water are removed, what was the relative humidity of the wet air?

One hundred students were asked what kind of music they like to listen to. The results...

One hundred students were asked what kind of music they like to listen to. The results are in the table below. Classical Rock Jazz Folk Female 2 13 15 2 Male 7 14 3 4 If one student is selected randomly, find the following probabilities: a) Student is a female b) Student likes classical music c) Student is a female and likes classical music d) Student likes classical music given she is female e) Are the events “female”...

Subjects