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Please help!
P(A) = 1/3
P(B) = 2/9
P(A U B) = 4/9
Find P(A ∩ B).
A. 1
B. 1/3
C. 1/9
D. 20/18

Respuesta :

Answer:

[tex]\sf C. \quad \dfrac{1}{9}[/tex]

Step-by-step explanation:

Addition Law for Probability

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

Given:

  [tex]\sf P(A)=\dfrac{1}{3}=\dfrac{3}{9}[/tex]

  [tex]\sf P(B)=\dfrac{2}{9}[/tex]

  [tex]\sf P(A \cup B)=\dfrac{4}{9}[/tex]

Substitute the given values into the formula and solve for P(A ∩ B):

[tex]\implies \sf P(A \cup B) = P(A)+P(B)-P(A \cap B)[/tex]

[tex]\implies \sf \dfrac{4}{9} = \sf \dfrac{3}{9}+\dfrac{2}{9}-P(A \cap B)[/tex]

[tex]\implies \sf P(A \cap B) = \sf \dfrac{3}{9}+\dfrac{2}{9}-\dfrac{4}{9}[/tex]

[tex]\implies \sf P(A \cap B) = \sf \dfrac{3+2-4}{9}[/tex]

[tex]\implies \sf P(A \cap B) = \sf \dfrac{1}{9}[/tex]

[tex]\\ \rm\leadsto P(A\cap B)=P(A)+P(B)-P(A\cup B)[/tex]

[tex]\\ \rm\leadsto P(A\cap B)=\dfrac{1}{3}+\dfrac{2}{9}-\dfrac{4}{9}[/tex]

[tex]\\ \rm\leadsto P(A\cap B)=\dfrac{3+2-4}{9}[/tex]

[tex]\\ \rm\leadsto P(A\cap B)=\dfrac{1}{9}[/tex]