Question

Choose all which define events A and B as independent events.

Answer 1

There are 2 answers: Choice 1, Choice 4

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Why is this? Because we use the rule

P(A & B) = P(A) * P(B)

which only works if events A and B are independent

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For the first answer choice,

P(A) * P(B) = 0.6*0.4 = 0.24 = P(A & B)

so that matches.

The same applies to the fourth answer choice as well

P(A) * P(B) = 0.3*0.2= 0.06 = P(A & B)

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The other answer choices don't match up.

The second answer choice has

P(A) * P(B) = 0.3*0.4 = 0.12 but that doesn't match with the 0.70 given

Similarly for the third answer choice,

P(A) * P(B) = 0.5*0.1 = 0.05 which doesn't match with the 0.60