A 180 meter long train crosses a man standing on the platform in 6 sec. What is the speed of the train?
Options:
(A) 229
(B) 108
(C) 278
(D) 126
(E) 112
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S = 180/6 * 18/5 = 108 kmph So the answer is: (B).
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A money lender lends Rs.2000 for six months at 20% p.a. rate. It the interest is reckoned quarterly than find the amount given after time limit.
Options:
(A) Rs.2205
(B) Rs.2200
(C) Rs.2160
(D) Rs.2040
(E) Rs.2050
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A = 2000(21/20)2 = 2205 So the answer is: (A).
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A train which has 390 m long, is running 45 kmph. In what time will it cross a person moving at 9 kmph in same direction ?
Options:
(A) 26 sec
(B) 39 sec
(C) 36 sec
(D) 29 sec
(E) 30 sec
--
Time taken to cross a moving person = length of train/ relative speed
Time taken = 390/((45-9) (5/18) = 390/ 36*(5/18) = 390/10 = 39 sec So the answer is: (B).
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