Which probabilities are correct? select two options. p(a|c) = two-thirds p(c|b) = startfraction 8 over 27 endfraction p(a) = startfraction 31 over 59 endfraction p(c) = three-sevenths p(b|a) = startfraction 13 over 27 endfraction

Respuesta :

Probability of an event is the measure of its chance of occurrence. The correct probabilities are:

  • P(A|C) = 2/3
  • P(C) = 3/7

How to interpret conditional probabilities?

Suppose that the sample space is S. Out of which there are two events, A and B, subsets of S.

Then, we can interpret P(A|B) as the probability of that part of A which is in B, with the new sample space as B. (assuming probabililty of B isn't 0).

Symbolically, we write it as:

[tex]P(A|B) = \dfrac{P(A \cap B)}{P(B)}[/tex]

What is the size of the union of three sets?

For three sets, A, B and C:

[tex]n(A \cup B \cup C) = n(A) + P(B) + P(C) - n(A\cap B) - n(A \cap C) - n(B \cap C) + n(A \cap B \cap C)[/tex]

The problem is incomplete. The corresponding venn diagram is attached below.

We can symbolize the venn diagram as:

[tex]n(A) = 12+8+6+5 =31\\n(B) = 11+8+5+3 = 27\\n(C) = 4+8+6+3 = 21\\n(A \cap B) = 5+8=13\\n(B\cap C) = 3+8=11\\n(A \cap C) = 6+8=14\\n(A \cap B \cap C) = 8[/tex]

S = sample space = collection of all unique elements.

S is union of A, B and C.

[tex]n(S) = n(A \cup B\cup C) = 31 + 27 + 21 -13-11-14+8 = 49[/tex]

Checking all the options for their correctness:

  • P(A|C) = 2/3

We have:

[tex]P(A|C) = P(A\cap C)/P(C) = \dfrac{n(A\cap C)/n(S)}{n(C)/n(S)} = \dfrac{n(A \cap C)}{n(C)} = \dfrac{14}{21} =\dfrac{2}{3}[/tex]

Thus, its correct.

  • P(C|B) = 8/27

[tex]P(C|B) = P(C\cap B)/P(B) = \dfrac{n(C\cap B)/n(S)}{n(B)/n(S)} = \dfrac{n(C \cap B)}{n(B)} = \dfrac{11}{27} \neq \dfrac{8}{27}[/tex]

Thus, this option is incorrect.

  • [tex]P(A) = \dfrac{n(A)}{n(S)} = \dfrac{31}{49} \neq \dfrac{31}{59}[/tex]

Thus, this option is incorrect.

  • P(C) = 3/7

[tex]P(C) = \dfrac{n(C)}{n(S)}= \dfrac{21}{49} =\dfrac{3}{7}[/tex]

Thus, its correct.

  • P(B|A) = 13/27

[tex]P(B|A) = P(B\cap A)/P(A) = \dfrac{n(B\cap A)/n(S)}{n(A)/n(S)} = \dfrac{n(B\cap A)}{n(A)} = \dfrac{13}{31} \neq \dfrac{13}{27}[/tex]

Thus, this option is incorrect.

Thus, the correct probabilities are:

  • P(A|C) = 2/3
  • P(C) = 3/7

Learn more about probability here:

brainly.com/question/1210781

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Answer:

A. P(A) = 3/5

Step-by-step explanation:

i did it

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