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Answer the following: Ten students are to be selected for a project from a class of 30 stdudents. There are 4 students who want to be together either in the project or not in the project. Find the nu - Mathematics and Statistics

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Question

Answer the following:

Ten students are to be selected for a project from a class of 30 students. There are 4 students who want to be together either in the project or not in the project. Find the number of possible selections

Sum
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Solution

Case I Case II
4 Students are in 4 Students are out
Number of ways = 26C6 Number of ways = 26C10

Required number = 26C6 + 26C10

= 230230 + 5311735

= 5541965

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Properties of Combinations
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Chapter 3: Permutations and Combination - Miscellaneous Exercise 3.2 [Page 68]

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Balbharati Mathematics and Statistics 2 (Arts and Science) [English] Standard 11 Maharashtra State Board
Chapter 3 Permutations and Combination
Miscellaneous Exercise 3.2 | Q II. (6) | Page 68

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