P(A) = 1/2, P(B) = 1/3 and P(A B) = 1/6. What is P(A B)?

Question 55

EasyOriginal question

$P(A) = \frac{1}{2}$ , $P(B) = \frac{1}{3}$ and $P(A \cap B) = \frac{1}{6}$ . What is $P(A \cup B)$ ?

\frac{1}{6}

Correct answerYour answer

\frac{1}{3}

Correct answerYour answer

\frac{2}{3}

Correct answerYour answer

\frac{5}{6}

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

$P(A \cup B) = P(A) + P(B) - P(A \cap B)$ .
$= \frac{1}{2} + \frac{1}{3} - \frac{1}{6} = \frac{3 + 2 - 1}{6} = \frac{2}{3}$ .

Worth noting

$\frac{5}{6}$ adds without taking off the overlap, which is then counted twice.

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