1. Among employees of a certain company, 60% know C/C++, 50% know R, 30% know both languages, and 20% know neither language. Let A = "knows C/C++" and B = "knows R". Are events A and B independent? Explain. a. Yes, because P(A and B) = P(A)P(B) = 0.6 x 0.5 = 0.3

b. No, they are dependent because an employee should know both languages.

c. Yes. they are dependent because an employee should know both languages.

d. No, because P(A and B) = P(A)P(B) = 0.6 x 0.5 0.2

2. Among employees of a certain company, 60% know C/C++, 50% know R, 30% know both languages, and 20% know neither language. Let A = "knows C/C++" and B = "knows R".

a. What is the probability that a randomly chosen employee knows R but not C/C++ ?

b. What is the probability that a randomly chosen employee knows C/C++ or they know R?