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How Many Different Selections of 4 Books Can Be Made from 10 Different Books, Ifthere is No Restriction;

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Question

How many different selections of 4 books can be made from 10 different books, if
there is no restriction;

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Solution

Required ways of selecting 4 books from 10 books without any restriction =\[{}^{10} C_4 = \frac{10}{4} \times \frac{9}{3} \times \frac{8}{2} \times 7 = 210\]

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Chapter 17: Combinations - Exercise 17.2 [Page 16]

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R.D. Sharma Mathematics [English] Class 11
Chapter 17 Combinations
Exercise 17.2 | Q 8.1 | Page 16

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