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प्रश्न
The number of ways in which a host lady can invite for a party of 8 out of 12 people of whom two do not want to attend the party together is
पर्याय
2 × 11C7 + 10C8
10C8 + 11C7
12C8 − 10C6
none of these
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उत्तर
12C8 − 10C6
A host lady can invite 8 out of 12 people in
∴ Number of ways = 12C8 − 10C6
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