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Compute: L.C.M. (6!, 7!, 8!)

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Question

Compute:

 L.C.M. (6!, 7!, 8!)

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Solution

 LCM of (6!,7! and 8!):
 n! = n(n - 1 )!
Therefore, (6!,7! and 8!) can be rewritten as:

8! = 8 X 7 X 6 !

7!= 7 X 6!

6!= 6!

∴ LCM of  (6!,7! and 8!) = LCM  [8 x 7 x 6!, 7 x 6!] = 8 x 7 x 6 ! = 8!

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Chapter 16: Permutations - Exercise 16.1 [Page 4]

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R.D. Sharma Mathematics [English] Class 11
Chapter 16 Permutations
Exercise 16.1 | Q 1.3 | Page 4

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