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# Basic probability

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2. (Original post by khanpatel321)

Shouldn't Pr(AuB) = 0.3

0.5+0.2 - 0.4 = 0.3 ?
0.5 + 0.2 - 0.4 is .
3. (Original post by khanpatel321)

Shouldn't Pr(AuB) = 0.3

0.5+0.2 - 0.4 = 0.3 ?
P(B) is not 0.2, it's 0.6.
4. (Original post by SeanFM)
0.5 + 0.2 - 0.4 is .
(Original post by notnek)
P(B) is not 0.2, it's 0.6.
Thanks

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