q: The speed of a train is 90 kmph. What is the distance covered by it in 20 minutes?
Options:
(A) 15
(B) 66
(C) 77
(D) 30
(E) 42
a: Stream of consciousness: 90 * 20/60 = 30 kmph The answer is (D).
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q: A 600 meter long train crosses a signal post in 60 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?
Options:
(A) 4 min
(B) 2 min
(C) 6 min
(D) 9 min
(E) 5 min
a: Stream of consciousness: S = 600/60 = 10 mps
S = 3600/10 = 360 sec = 6 min The answer is (C).
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q: Two trains are moving at 65 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) 6 2/3 sec
(B) 7 1/7 sec
(C) 7 2/2 sec
(D) 8 1/2 sec
(E) 7 1/9 sec
a:
Stream of consciousness: 70 + 65 = 135 * 5/18 = 75/2 mps
D = 150 + 100 = 250 m
T = 250 * 2/75 = 20/3 - 6 2/3 sec The answer is (A).
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