SOLUTION: find n if p(n,4)=12p(n,2)

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Question 1118297: find n if p(n,4)=12p(n,2)
Answer by math_helper(2461) About Me  (Show Source):
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Ans: +highlight%28+n=6+%29+
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Workout:
+n%21%2F%28n-4%29%21+=+12%28n%21%2F%28n-2%29%21%29+

Divide both sides by n!:
++1%2F%28n-4%29%21++=+12%2F%28n-2%29%21+

Re-arrange to:
++12%28n-4%29%21+=+%28n-2%29%21+
++4%2A3%2A%28n-4%29%21+=+%28n-2%29%21+
Logically, the left hand side needs to be +4%2A3%2A2%2A1+
which implies n-4 = 2 ==> n=6
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Check: P(6,4) = 360
12P(6,2) = 12*30 = 360
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