English

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 (A) 2 × 11c7 + 10c8 (B) 10c8 + 11c7 (C) 12c8 − 10c6

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Question

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

Options

  •  2 × 11C7 + 10C8

  • 10C8 + 11C7

  • 12C8 − 10C6

  • none of these

MCQ
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Solution

12C8 − 10C6

A host lady can invite 8 out of 12 people in 

\[{12}_{C_8}\]
 ways. Two out of these 12 people do not want to attend the party together.
∴ Number of ways = 12C8 − 10C6
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Chapter 17: Combinations - Exercise 17.5 [Page 26]

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R.D. Sharma Mathematics [English] Class 11
Chapter 17 Combinations
Exercise 17.5 | Q 18 | Page 26

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