Example 7 - Chapter 6 Class 11 Permutations and Combinations

Last updated at July 20, 2026 by

Example 7 - Evaluate n!/r!(n - r)! when n = 5, r = 2 - Examples - Examples

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Example 7 Evaluate n!/r!(n r)! when n = 5, r = 2. !/ !( )! Putting n = 5, r = 2 5!/2!(5 2)! = 5!/(2! 3!) = (5 4 3!)/(2! 3!) = (5 4 )/(2 1 ) = 20/2 = 10

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