q: A train 260 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
Options:
(A) 40
(B) 32
(C) 26
(D) 21
(E) 14
a: Speed = 45 * 5/18 = 25/2 m/sec
Total distance covered = 260 + 140 = 400 m
Required time = 400 * 2/25 = 32 sec The answer is (B).
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q: In what time a sum of money double itself at 8% per annum simple interest?
Options:
(A) 33 1/8%
(B) 33 1/3%
(C) 33 7/3%
(D) 32 1/3%
(E) 12 1/2%
a: P = (P*8*R)/100
R = 12 1/2% The answer is (E).
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q: A 600 meter long train crosses a signal post in 20 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) 9 min
(E) 5 min
a: S = 600/20 = 1530 mps
S = 3600/30 = 120 sec = 2 min The answer is (B).
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q: The speed of a car is 120 km in the first hour and 60 km in the second hour. What is the average speed of the car?
Options:
(A) 89 kmph
(B) 92 kmph
(C) 90 kmph
(D) 65 kmph
(E) 77 kmph
a:
S = (120 + 60)/2 = 90 kmph The answer is (C).
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