Carmen Homework 6 - Probability Rules

Thomas wants to know what percentage of females buy his product. Thomas knows his customers are 50% male and 50% female, and that 30% of all his customers buy his product. He collects data on people who have already bought his product, and asks their gender. He finds that 70% of the people who bought his product were female. What method would you use to answer Thomas' original question?

Bayes' Rule

Suppose 40% of all OSU students own a Tablet PC and an iPhone. Write this as a probability.

None of the answers provided.

Suppose a school figures that 70% of adults will purchase a candy bar from a 6th grader during a fund-raiser. A sixth grader randomly selects 10 adults. What's the chance that at least one of them will buy a candy bar?

None of the answers provided.

Suppose 70% of Facebook users have Twitter accounts. Write this as a probability.

P(Twitter | Facebook) = 0.70

Which of the following is the complement of "at most 1"?

"More than 1"

Suppose 40% of OSU students have internships over the summer, and of those who have internships, 60% of them are business majors. What percentage of all OSU students are business students and have internships over the summer?

24%

Suppose 20% of OSU students are business majors, and of the business majors, 60% have internships over the summer. Of those who are not business majors, 30% have internships over the summer. What percentage of ALL students have internships over the summer?

36%

Bob and Bill live in an apartment together. Bob is in the apartment 30% of the time overall. But when Bill is in the apartment, Bob is only there 10% of the time. Let Event A = "Bill is in the apartment", and let Event B = "Bob is in the apartment." Are Events A and B independent?

No

If A and B are independent, all you need is P(A) and P(B) to calculate P(A or B).

True

If 60% of male-owned businesses are successful in their first year, and 60% of female-owned businesses are successful in their first year, are gender and having a successful business in their first year independent?

Yes