SOLUTION: What is n in the equation? n!/84 = (n-2)!/[(n-2)-(n-4)] do I cancel n-2 and n-4 on the right side?

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Question 1139281: What is n in the equation?
n!/84 = (n-2)!/[(n-2)-(n-4)]
do I cancel n-2 and n-4 on the right side?
Answer by greenestamps(13198) About Me  (Show Source):
You can put this solution on YOUR website!


You can't cancel the (n-2) and (n-4) in the denominator on the right; they are not factors.

The denominator on the right is simply (n-2)-(n-4) = 2.

Then write the n! on the left as n(n-1)(n-2)!; do some canceling of common factors; cross-multiply; and solve.