If (n+2)!/n!=156, n=?
Choose one
A) 2/131 B) 9 C) 10 D) 11 E) 12
(n+2)!/n!= 156   Rewrite as:[(n+2)(n+1)(n)(n-1)(n-2)....(3)(2)(1)]/[(n)(n-1)(n-2)....(3)(2)(1)]= 132   Cancel out terms: (n+2)(n+1) = 156   From here, we might just TEST the answer choices.   Since (13)(12) = 156, we can see that n = 11   11
<result>D</result>
If (n+2)!/n!=156, n=?