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Question
Evaluate: `("n"!)/("r"!("n" - "r"!)` For n = 8, r = 6
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Solution
n = 8, r = 6
`("n"!)/("r"!("n" - "r"!)) = (8!)/(6!(8 - 6!))`
= `(8 xx 7 xx 6!)/(2!6!)`
= `(8 xx 7)/(2!)`
= `(8xx7)/(1xx2)`
= 28
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