Q: Which of the following is equal to (x+1)!/x!
Options:
(A) x-1
(B) 1+(1/x) 
(C) x+1
(D) 1
(E) x
A: OK... Stream of consciousness: (x + 1)! = (x + 1) * x!
(x + 1)!/x! = x + 1
The answer is (C).

Q: How many seconds will a train 100 meters long take to cross a bridge 180 meters long if the speed of the train is 36 kmph?
Options:
(A) 54 sec
(B) 28 sec
(C) 25 sec
(D) 45 sec
(E) 24 sec
A: OK... Stream of consciousness: D = 100 + 180 = 280
S = 36 * 5/18 = 10 mps
T = 280/10 = 28 sec
The answer is (B).

Q: The measure of the side of a square is tripled. If x represents the perimeter of the original square, what is the value of the new perimeter?
Options:
(A) 3x
(B) 4x
(C) 9x
(D) 12x
(E) 27x
A: OK... Stream of consciousness: Original perimeter = x
Hence original side = x/4
New side = 3x/4
New perimeter = 4*3x/4 = 3x
The answer is (A).

Q: An analyst will recommend a combination of 4 industrial stocks, 2 transportation stocks, and 2 utility stocks. If the analyst can choose from 5 industrial stocks, 4 transportation stocks, and 3 utility stocks, how many different combinations of 8 stocks are possible?
--
Options:
(A) 12
(B) 19
(C) 90
(D) 180
(E) 720
A:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
OK... Stream of consciousness: 5C4 * 4C2 * 3C2 = 5*6*3 = 90.
The answer is (C).