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प्रश्न
In a family, the husband tells a lie in 30% cases and the wife in 35% cases. Find the probability that both contradict each other on the same fact.
उत्तर
It is given that the husband lies in 30% of the cases, while the wife lies in 35% cases
\[P\left( \text{ both will contradict each other on the same fact } \right) = P\left( \text{ husband lies but wife tells the truth } \right) + P\left( \text{ wife lies buthusband tells the truth } \right)\]
\[ = 0 . 3 \times \left( 1 - 0 . 35 \right) + \left( 1 - 0 . 3 \right) \times 0 . 35\]
\[ = 0 . 3 \times 0 . 65 + 0 . 7 \times 0 . 35\]
\[ = 0 . 195 + 0 . 245\]
\[ = 0 . 44\]
`= 44 %`
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