If P,(A) = 0.4,,,P,(B) = x,,,P,(A cup B) = 0.7 and events A and B are independent, then x =

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14.Probability

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If $P\,(A) = 0.4,\,\,P\,(B) = x,\,\,P\,(A \cup B) = 0.7$ and the events $A$ and $B$ are independent, then $x =$

A

$\frac{1}{3}$

B

$\frac{1}{2}$

C

$\frac{2}{3}$

D

None of these

Solution

(b) $0.7 = 0.4 + x – 0.4x \Rightarrow x = \frac{1}{2}.$

Standard 11

Mathematics

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