q: If 10x = 8y = 14z, then what is a possible sum of positive integers x, y, and z?
Options:
(A) 52
(B) 166
(C) 84
(D) 122
(E) 168
a: Stream of consciousness: 10x = 8y = 14z
5x = 4y = 7z
5(4*7) = 4(5*7) = 7(5*4)
Addition = 28+20+35 = 83
Answer would be multiple of 83 which is 166 The answer is (B).

question: Four of the following five parts numbered (a), (b), (c), (d) and (e) are exactly equal. The number of the part which is not equal to the other four parts is your answer.
Options:
(A) 85 17 110
(B) 45 6 + 75 4
(C) 175 25 75 + 5(2)
(D) 36 4 + 21(2) 7 5
(E) 65 12 46 5
answer: Stream of consciousness: Except it, others are equal to 550. The answer is (B).

q: If six persons sit in a row, then the probability that three particular persons are always together is ?
Options:
(A) 1/6
(B) 1/2
(C) 1/5
(D) 1/2
(E) 1/1
a: Stream of consciousness: Six persons can be arranged in a row in 6! ways. Treat the three persons to sit together as one unit then there four persons and they can be arranged in 4! ways. Again three persons can be arranged among them selves in 3! ways. Favourable outcomes = 3!4! Required probability = 3!4!/6! = 1/5 The answer is (C).

question: Two trains are moving at 60 kmph and 70 kmph in opposite directions. Their lengths are 150 m and 100 m respectively. The time they will take to pass each other completely is?
Options:
(A) 5 sec
(B) 6 sec
(C) 7 sec
(D) 8 sec
(E) 9 sec
answer: Stream of consciousness: 70 + 60 = 130 * 5/18 = 325/9 mps
D = 150 + 100 = 250 m
T = 250 * 9/325 = 7 se The answer is (C).

q: A 600 meter long train crosses a signal post in 40 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?
Options:
(A) 4 min
(B) 8 min
(C) 9 min
(D) 6 min
(E) 1 min
a: Stream of consciousness: S = 600/40 = 15 mps
S = 3600/15 = 240 sec = 4 min The answer is (A).

q: The average of 13 numbers is 60. Average of the first 7 of them is 54 and that of the last 7 is 61. Find the 8th number?
Options:
(A) 25
(B) 83
(C) 45
(D) 53
(E) 64
a:
Stream of consciousness: Sum of all the 13 numbers = 13 * 60 = 780
Sum of the first 7 of them = 7 * 54 = 378
Sum of the last 7 of them = 7 * 61 = 427
So, the 8th number = 427 + 378 - 780 = 25. The answer is (A).