How many seconds will a train 100 meters long take to cross a bridge 170 meters long if the speed of the train is 36 kmph?
Options:
(A) 54 sec
(B) 65 sec
(C) 25 sec
(D) 45 sec
(E) 27 sec
--
D = 100 + 170 = 270
S = 36 * 5/18 = 10 mps
T = 270/10 = 27 sec So the answer is: (E).
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A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 70 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 70 minutes
(D) 28 minutes
(E) 11 minutes
--
1/20 - 1/70 = 1/28
28 minutes So the answer is: (D).
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Rajani has to read a book of 445 pages. She has already read the first 157 pages of the book and if she reads 24 pages of the book everyday then how long will she take now to complete the book?
Options:
(A) 25 days
(B) 20 days
(C) 46 days
(D) 21 days
(E) None of these
--
Remaining pages to read = 445 157 = 288
Reqd. number of days = 28824 = 12 So the answer is: (E).
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