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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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