Reasoning: Speed downstream = 30+ 20 = 50 kmph
Speed upstream = 30 - 20 = 10 kmph
Ans: (B)
Question: The speed of a boat in still water is 30kmph and the speed of the current is 20kmph. Find the speed downstream and upstream?
Options:
(A) kmph
(B) kmph
(C) kmph
(D) kmph
(E) kmph
Rationale: Plug in an odd integer; in this case 3
(2*3)-3 = 3 Odd
3+1 = 4 Even
(2*3)+3 = 9 Odd
3^3 = 27 Odd
(3*3)+(2*3) = 9 + 6 = 15 Odd
The answer: (B)
Question: If x is an odd integer, which of the following is an even integer?
Options:
(A) 2x-x
(B) x+1
(C) 2x+3
(D) x^3
(E) 3x+2x
Reasoning: D = 130 + 150 = 280
S = 36 * 5/18 = 10 mps
T = 280/10 = 28 sec
Ans: (A)
Question: How many seconds will a train 130 meters long take to cross a bridge 150 meters long if the speed of the train is 36 kmph?
Options:
(A) 28 sec
(B) 23 sec
(C) 24 sec
(D) 25 sec
(E) 26 sec
Rationale: Total number of ways = 6!*2!.
The answer: (C)
Question: There are 9 person among whom 2 are brother. The total no.of ways in which these persons can be seated around a round table so that exactly 1person sit between the brothers, is equal to?
Options:
(A) 4!*2!
(B) 7!*2!
(C) 6!*2!
(D) 2!*1!
(E) 5!*1!
Reasoning: N ends in the digit 1 because when N is divided by 10, the remainder is 1. Since N ends in 1, the remainder G when N is divided by 30 also ends in a 1. 11 is the only choice which ends in a 1.
Ans: (C)
Question: When N is divided by 10 the remainder is 1 and when N is divided by 3 the remainder is 2. What is the remainder G when N is divided by 30?
Options:
(A) (a)  4
(B) (b)  7
(C) (c)  11
(D) (d)  13
(E) (e)  17
Reasoning: Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 280 * 2/35 = 16 sec
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 280 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 15 sec
(B) 16 sec
(C) 18 sec
(D) 20 sec
(E) 22 sec