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# Probability watch

1. If A and B are events with P(A) = 0.2 and P(B) = 5/6 how would I show that 1/30 ≤ P(A ∩ B) ≤ 0.2 ?
2. (Original post by Bruce Harrisface)
If A and B are events with P(A) = 0.2 and P(B) = 5/6 how would I show that 1/30 ≤ P(A ∩ B) ≤ 0.2 ?
think about the 2 extreme positions using a Venn diagram
3. (Original post by Bruce Harrisface)
If A and B are events with P(A) = 0.2 and P(B) = 5/6 how would I show that 1/30 ≤ P(A ∩ B) ≤ 0.2 ?
As P[A]+P[B]=1/5+5/6=31/30 and P[A or B] can't be greater than 1, P[A and B] is greater than or equals to 31/30-30/30=1/30. And because P[A]=0.2, the maximum of P[A and B] is 0.2.

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