Find the probability that it is a mystery or comedy.

Question

A media rental store rented the following number of movie titles in each of these categories: 162

 horror, 222

 drama, 116

 mystery, 322

 romance, and 134

 comedy. If a person selects a movie to rent, find the probability that it is a mystery or comedy.

Enter your answer as a fraction or a decimal rounded to 3

 decimal places.

P mystery or comedy

=

Answer 1

The way we calculate the probability that either event A or B occurs depends on whether or not events A and B are mutually exclusive or not. Two events are mutually exclusive if they cannot occur at the same time.

If A and B are mutually exclusive, then the formula we use to calculate P(A∪B) is: P(A∪B) = P(A) + P(B). Even though a movie could be a mystery and comedy at the same time, we will assume for the sake of the problem that these two events are mutually exclusive because the media rental store sorted the movies into individual, non-overlapping categories.

Therefore, P(mystery or comedy) is P(mystery) + P(comedy). You can find P(mystery) and P(comedy) respectively by dividing the number of movie titles in the category by the total number of movie titles sold at the rental store.

Hope this helps!