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प्रश्न
A candidate is required to answer 7 questions out of 12 questions which are divided into two groups, each containing 6 questions. He is not permitted to attempt more than 5 questions from either group. In how many ways can he choose the 7 questions?
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उत्तर
Required ways =
\[ = 2\left( 90 + 300 \right)\]
\[ = 2\left( 390 \right)\]
\[ = 780\]
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