Reasoning: (y + 1)! = (y + 1) * x!
(y + 1)!/y! = y + 1
Ans: (D)
Question: Which of the following is equal to (y+1)!/y!?
Options:
(A) y-1
(B) 1+(1/y) 
(C) 1
(D) y+1
(E) y
Rationale: Total cost involved for each 75 $ shipment: 3+2 = 5 $. Thus, for two such orders = 10$
Total cost involved for a 150$ shipment: 3+3 = 6$. Thus, for two such orders = 12$
The difference = 2$.
The answer: (B)
Question: For every order, a certain mail-order company charges a shipping fee of $3 plus an additional $2 if the value of the order is over $50 but not over $100 or an additional $3 if the value of the order is over $100. How much greater are the total shipping fees for 2 orders of $75 each than the total shipping fee for 2 order of $150 ?
Options:
(A)  $1
(B)  $2
(C)  $3
(D)  $4
(E)  $5
Reasoning: 10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!
Required probability = 1/5
Ans: (C)
Question: 10 books are placed at random in a shelf. The probability that a pair of books will always be together is?
Options:
(A) 1/0
(B) 1/3
(C) 1/5
(D) 1/2
(E) 1/1
Rationale: The probability that she hits the bullseye at least once = 1 - (the probability that she misses the bullseye every shot)
The probability that she misses every shot = (prob that she misses from 50 yards)*(prob that she misses from 60 yards)*(prob that she misses from 70 yards)
Prob that she misses from 50 yards = 1 - 3/4 = 1/4; Prob that she misses from 60 yards = 1 - 2/3 = 1/3; Prob that she misses from 70 yards = 1 - 3/5 = 2/5
Thus the probability that she misses all shots = (1/4)*(1/3)*(2/5) = 1/30
Thus the probability that she makes at least one shot = 1 - (1/30) = 29/30
The answer: (D)
Question: An archer is shooting arrows from various distances. She shoots at a target from 50 yards, 60 yards, and 70 yards. The probability that she hits within the bullseye from 50 yards is 3/4, the probability that she hits within the bullseye from 60 yards is 2/3, and the probability that she hits within the bullseye from 70 yards is 3/5. What is the probability that she hits the bullseye at least once in three shots, one from each distance listed.
Options:
(A) 9/10
(B) 14/15
(C) 19/20
(D) 29/30
(E) 39/40
Reasoning: Distance covered by the car = 65 × 10 = 650 km
\ Speed = 650⁄5 = 130 km/hr
\ Speed gain = 130 – 65 = 65 km/hr
Ans: (C)
Question: A car finishes a journey in ten hours at the speed of 65 km/hr. If the same distance is to be covered in five hours how much more speed does the car have to gain?
Options:
(A) 8 km/hr
(B) 10 km/hr
(C) 65 km/hr
(D) 16 km/hr
(E) None of these
Reasoning: D = 25 * 60 + 1500 = 3000 m
T = 3000/60 * 18/5 = 180 sec = 3 mins
Ans: (B)

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.
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Question: A train of 24 carriages, each of 60 meters length, when an engine also of 60 meters length is running at a speed of 60 kmph. In what time will the train cross a bridge 1.5 km long?
Options:
(A) 2 mins
(B) 3 mins
(C) 9 mins
(D) 8 mins
(E) 6 mins