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A group of people were asked if they enjoy going to concerts or movies.

The table shows the probabilities of the results.

A group of people were asked if they enjoy going to concerts or movies. The table-example-1
User Achempion
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2 Answers

3 votes
The correct answer is the second choice.

They are not independent because P(movies|concerts)=0.25 ≠ P(movies)=0.6, and P(concerts|movies)=0.25 ≠ P(concerts)=0.55
User Lyndonna
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6 votes

Answer:

Option: B is the correct answer.

Enjoying movies and concerts are not independent since,


P(movies|concerts)\\eq P(movies)

and
P(concerts|movies)\\eq P(concerts)

Explanation:

We know that if two events A and B are independent then:


P(A\bigcap B)=P(A)* P(B)

where P denote the probability of an event.

Now, we know that:


P(movies|concerts)=(P(movies\bigcap Concerts))/(P(concerts))

Similarly:


P(concerts|movies)=(P(movies\bigcap Concerts))/(P(movies))

If movies and concerts are independent then:


P(movies|concerts)=P(movies)

Similarly:


P(concerts|movies)=P(concerts)

We have:


P(movies)=0.6


P(concerts)=0.55


P(concerts|movies)=(0.25)/(0.6)


P(movies|concerts)=(0.25)/(0.55)

Hence,

Enjoying movies and concerts are not independent

Since,


P(movies|concerts)\\eq P(movies)

and
P(concerts|movies)\\eq P(concerts)

User Chris Tolworthy
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