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प्रश्न
A speaks the truth 8 times out of 10 times. A die is tossed. He reports that it was 5. What is the probability that it was actually 5?
उत्तर
Let A denote the event that man reports that 5 occurs and E the event that 5 actually turns up.
∴ P(E) = \[\frac{1}{6}\] \[P\left( \overline{ E } \right) = 1 - \frac{1}{6} = \frac{5}{6}\]
Also,
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