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Question
Evaluate : `("n"!)/("r"!("n" - "r")!)` for n = 8, r = 6
Solution
n = 8, r = 6
∴ `("n"!)/("r"!("n" - "r")!) = (8!)/(6!(8 - 6)!)`
= `(8!)/(6! xx 2!)`
= `(8 xx 7 xx 6!)/(6! xx 2 xx 1)`
= 28.
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