Respuesta :
Answer:
a) [tex] P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.3}{0.45}= 0.667[/tex]
Represent the probability that the event B occurs given that the event A occurs first
b) [tex] P(B'|A) = \frac{0.15}{0.45}=0.333[/tex]
Represent the probability that the event B no occurs given that the event A occurs first
c) [tex] P(A|B) = \frac{P(A \cap B)}{P(B)} = \frac{0.3}{0.35}= 0.857[/tex]
Represent the probability that the event A occurs given that the event B occurs first
d) [tex] P(A'|B) = \frac{0.05}{0.35}=0.143[/tex]
Represent the probability that the event A no occurs given that the event B occurs first
Step-by-step explanation:
For this case we have the following probabilities given for the events defined A and B
[tex] P(A) = 0.45, P(B) = 0.35, P(A \cap B) =0.30[/tex]
For this case we can begin finding the probability for the complements:
[tex] P(B') =1-P(B) = 1-0.35= 0.65[/tex]
[tex] P(A') =1-P(A) = 1-0.45= 0.55[/tex]
For this case we are interested on the following probabilities:
Part a
[tex] P(B|A)[/tex]
For this case we can use the Bayes theorem and we can find this probability like this:
[tex] P(B|A) = \frac{P(A \cap B)}{P(A)} = \frac{0.3}{0.45}= 0.667[/tex]
Represent the probability that the event B occurs given that the event A occurs first
Part b
[tex] P(B'|A) = \frac{P(B' \cap A)}{P(A}[/tex]
And for this case we can find [tex] P(B' \cap A) =P(A) -P(A\cap B)= 0.45-0.3=0.15[/tex]
And if we replace we got:
[tex] P(B'|A) = \frac{0.15}{0.45}=0.333[/tex]
Represent the probability that the event B no occurs given that the event A occurs first
Part c
[tex] P(A|B) = \frac{P(A \cap B)}{P(B)} = \frac{0.3}{0.35}= 0.857[/tex]
Represent the probability that the event A occurs given that the event B occurs first
Part d
[tex] P(A'|B) = \frac{P(A' \cap B)}{P(B}[/tex]
And for this case we can find [tex] P(A' \cap B) =P(B) -P(A\cap B)= 0.35-0.3=0.05[/tex]
And if we replace we got:
[tex] P(A'|B) = \frac{0.05}{0.35}=0.143[/tex]
Represent the probability that the event A no occurs given that the event B occurs first