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Suppose two independent events A and B have the following probabilities: P(Aᶜ = 0.40 and P(B∣A) = 0.80. Compute the probability that either avent A accurs, or Boccurs, or both occur.

User Ramunas
by
8.1k points

1 Answer

4 votes

Answer:

neither A nor B will occur simultaneously, as they are mutually exclusive.

Explanation:

To compute the probability that either event A occurs, or B occurs, or both occur, you can use the principle of the union of events. The probability of the union of two events A and B (denoted as A ∪ B) can be calculated as:

(

)

=

(

)

+

(

)

(

)

P(A∪B)=P(A)+P(B)−P(A∩B)

In this case, you're given:

(

)

=

0.40

P(A

)=0.40, which means the probability of the complement of A (i.e., the probability that A does not occur).

(

)

=

0.80

P(B∣A)=0.80, which is the conditional probability of B occurring given that A has occurred.

Let's break it down:

(

)

P(A

) is the probability that event A does not occur, which is

1

(

)

1−P(A).

(

)

P(B∣A) is the conditional probability that event B occurs given that A has occurred.

So, you can calculate

(

)

P(A) and

(

)

P(B) as follows:

(

)

=

1

(

)

=

1

0.40

=

0.60

P(A)=1−P(A

)=1−0.40=0.60

Now, you can use the formula for the union of events to calculate

(

)

P(A∪B):

(

)

=

(

)

+

(

)

(

)

P(A∪B)=P(A)+P(B)−P(A∩B)

But before we calculate

(

)

P(A∩B), note that events A and B are independent, so

(

)

=

(

)

(

)

P(A∩B)=P(A)⋅P(B∣A).

(

)

=

(

)

(

)

=

0.60

0.80

=

0.48

P(A∩B)=P(A)⋅P(B∣A)=0.60⋅0.80=0.48

Now, plug this value into the formula:

(

)

=

0.60

+

(

)

0.48

P(A∪B)=0.60+P(B)−0.48

Solve for

(

)

P(B):

(

)

=

(

)

+

0.48

0.60

P(B)=P(A∪B)+0.48−0.60

(

)

=

(

)

0.12

P(B)=P(A∪B)−0.12

Now, you have the equation:

(

)

=

0.60

+

(

)

0.12

0.48

P(A∪B)=0.60+P(A∪B)−0.12−0.48

Simplify:

(

)

=

0.60

0.12

0.48

P(A∪B)=0.60−0.12−0.48

(

)

=

0.00

P(A∪B)=0.00

So, the probability that either event A occurs, or B occurs, or both occur is 0.00. This means that neither A nor B will occur simultaneously, as they are mutually exclusive.

User Pooja Mokariya
by
7.6k points