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Question
Mark the correct alternative in the following question:
If two events are independent, then
Options
they must be mutually exclusive
the sum of their probabilities must be equal to 1
(a) and (b) both are correct
none of the above is correct
Solution
\[\text{ Let A and B are two independent events . Then, } \]
\[P\left( A \cap B \right) = P\left( A \right) \times P\left( B \right)\]
\[\text{ As } , P\left( A \cap B \right) \neq 0 \text{ or } P\left( A \right) + P\left( B \right) \neq 1\]
\[\text{ So, both are neither mutually exclisive nor their sum of probabilities is 1 .} \]
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