q: A train 455 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 22 sec
(B) 16 sec
(C) 17 sec
(D) 39 sec
(E) 12 sec
a: Stream of consciousness: Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 455 * 2/35 = 39 sec The answer is (D).
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q: Find the least number must be added to 228712 so that remaining no.is divisible by 9?
Options:
(A) 5
(B) 3
(C) 1
(D) 6
(E) 2
a: Stream of consciousness: On dividing 228712 by 9 we get the remainder 4, so 5 should be subtracted The answer is (A).
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q: A can do a piece of work in 6 hours; B and C together can do it in 4 hours, which A and C together can do it in 3 hours. How long will B alone take to do it?
Options:
(A) 8hours
(B) 6hours
(C) 14hours
(D) 12hours
(E) 5hours
a:
Stream of consciousness: A's 1 hour work = 1/6;
(B + C)'s 1 hour work = 1/4;
(A + C)'s 1 hour work = 1/3
(A + B + C)'s 1 hour work = (1/4 + 1/6) = 5/12
B's 1 hour work = (5/12 - 1/3) = 1/12
B alone will take 12 hours to do the work. The answer is (D).
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