Chapter 6.6, Problem 79E

The report “Twitter in Higher Education: Usage Habits and Trends of Today’s College Faculty” (Magna Publications, September 2009) describes results of a survey of nearly 2000 college faculty. The report indicates the following:

• 30.7% reported that they use Twitter and 69.3% said that they did not use Twitter.
• Of those who use Twitter, 39.9% said they sometimes use Twitter to communicate with students.
• Of those who use Twitter, 27.5% said that they sometimes use Twitter as a learning tool in the classroom.

Consider the chance experiment that selects one of the study participants at random and define the following events:

T = event that selected faculty member uses Twitter

C = event that selected faculty member sometimes uses Twitter to communicate with students

L = event that selected faculty member sometimes uses Twitter as a learning tool in the classroom

1. a. Use the given information to calculate the following probabilities:
   1. i. P(T)
   2. ii. P(T^C)
   3. iii. P(C|T)
   4. iv. P(L|T)
   5. v. P(C ∩ T)
2. b. Interpret each of the probabilities computed in Part (a).