q: A 600 meter long train crosses a signal post in 30 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) 8 min
(D) 3 min
(E) 5 min
a: Stream of consciousness: S = 600/30 = 20 mps
S = 3600/20 = 180 sec = 4 min The answer is (D).
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q: A = 10% of x, B = 10% of y, C = 10% of x + 10% of y. On the basis of the above equalities, what is true in the following?
Options:
(A) A is equal to B
(B) A is greater than B
(C) B is greater than A
(D) Relation cannot be established between A and B
(E) None of these
a: Stream of consciousness: The given information gives no indication regarding the comparison of x and y. The answer is (D).
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q: Two trains are traveling on parallel tracks in the same direction. The faster train travels at 130 miles per hour, while the slower train travels at 100 miles per hour. At 2 o'clock the faster train is 15 miles behind the slower one. How far apart are the two trains at 5 o'clock?
Options:
(A) 60 miles
(B) 80 miles
(C) 75 miles
(D) 120 miles
(E) 400 miles
a:
Stream of consciousness: Answer = C. 75 miles
Relational speed = 130 - 100 = 30 miles per hour
In 3 hours, difference = 30 * 3 = 90 miles
Fast train trailing 15 miles, so effective difference = 90 - 15 = 75 miles The answer is (C).
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