A train 140 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 18 sec
(B) 6 sec
(C) 8 sec
(D) 15 sec
(E) 7 sec
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Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 140 * 2/35 = 8 se So the answer is: (C).
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Suppose you have three identical prisms with congruent equilateral triangles as the end-polygons. Suppose you attach them by the rectangular faces so they are perfectly aligned. There will be some large faces created by two or more co-planar faces of the individual prisms: count each such large face as one. Given that, how many faces does the resultant solid have
Options:
(A) 4
(B) 6
(C) 9
(D) 10
(E) 5
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To arrange them as described I did as follows on my scratch paper (see the file attached), where I counted 4 sides and bottom, hence 4+1 = 5. So the answer is: (E).
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The H.C.F. of two numbers is 12 and their L.C.M. is 520. If one of the numbers is 480, then the other is:
Options:
(A) 13
(B) 18
(C) 21
(D) 24
(E) 38
--
Other number = (12 x 520)/480 = 13. So the answer is: (A).
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