q: A man rows his boat 85 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?
Options:
(A) 6 kmph
(B) 5 kmph
(C) 2 kmph
(D) 8 kmph
(E) 1 kmph
a: Speed downstream = d/t = 85/(2 1/2) = 34 kmph
Speed upstream = d/t = 45/(2 1/2) = 18 kmph
The speed of the stream = (34 - 18)/2 = 8 kmph The answer is (D).
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q: A 240 meter long train crosses a man standing on the platform in 6 sec. What is the speed of the train?
Options:
(A) 228
(B) 144
(C) 1266
(D) 188
(E) 211
a: S = 240/6 * 18/5 = 144 kmph The answer is (B).
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q: A man sells two articles for Rs.3600 each and he gains 30% on the first and loses 30% on the next. Find his total gain or loss?
Options:
(A) 9% loss
(B) 400
(C) 4000
(D) 324
(E) 200
a: (30*30)/100 = 9%loss The answer is (A).
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q: The average of 11 results is 50, if the average of first six results is 49 and that of the last six is 52. Find the sixth result?
Options:
(A) 22
(B) 56
(C) 44
(D) 55
(E) 81
a:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
1 to 11 = 11 * 50 = 550
1 to 6 = 6 * 49 = 294
6 to 11 = 6 * 52 = 312
6th = 294 + 312 – 550 = 56 The answer is (B).
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