During a recent worknight between 9 PM and 10PM a regional t

During a recent worknight between 9 PM and 10PM, a regional television rating service claimed numbers of telivision sets were tuned in to major networks were as given below. What is the probability that a tevision set in use were tuned into CBS during the time period ?

Networks No of TV sets 9millions)

ABC 3.1

CBS 6.3

NBC 1.7

All other 2.4

Solution

There are a total of 2.1 + 6.3 + 1.7 + 2.4 = 12.5 million TV\'s.

Now, there are 6.3 million tuned in to CBS, so

P(CBS) = 6.3/12.5 = 0.504 [ANSWER]