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Question
Two coins are tossed once. Find P (A/B) in each of the following:
A = No tail appears, B = No head appears.
Solution
Consider the given events.
A = No tail appears
B = No head appears
Clearly,
A = {(H, H)}
B = {(T, T)}
\[\text{ Now} , \]
\[A \cap B = \left\{ \phi \right\}\]
\[ \therefore \text{ Required probability } = P\left( A/B \right) = \frac{n\left( A \cap B \right)}{n\left( B \right)} = \frac{0}{1} = 0\]
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