q: Two trains are moving at 50 kmph and 70 kmph in opposite directions. Their lengths are 170 m and 100 m respectively. The time they will take to pass each other completely is?
Options:
(A) 3 sec
(B) 8 sec
(C) 9 sec
(D) 5 sec
(E) 7 sec
a: Stream of consciousness: 70 + 50 = 120 * 5/18 = 100/3 mps
D = 170 + 100 = 270 m
T = 270 * 3/100 = 8 sec The answer is (B).
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q: If L is the least positive integer that is divisible by every integer from 1 to 9 inclusive, then L/2 is =
Options:
(A) 5040
(B) 2520
(C) 1890
(D) 1260
(E) 630
a: Stream of consciousness: The integer should be divisible by: 2, 3, 4, 5, 6, 7, 8 and 9, that is 2, 3, 2^2, 5, 2*3, 7, 2^3 and 3^2. The least common multiple of these integers is the product of 7, 5, 3^2 and 2^3. Then, L/2 is (7 * 5 * 3^2 * 2^3)/2 = 7*5*9*4 = 1260. The answer is (D).
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q: BCB, DED, FGF, HIH, ___
Options:
(A) KOP
(B) QLM
(C) JKJ
(D) PSQ
(E) IOP
a:
Stream of consciousness: This series consists of a simple alphabetical order with the first two letters of all segments: B, C, D, E, F, G, H, I, J, K. The third letter of each segment is a repetition of the first letter. The answer is (C).
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