q: A man, a woman and a boy can complete a job in 3, 4 and 12 days respectively. How many boys must assist 1 man and 1 woman to complete the job in 1/4 of a day?
Options:
(A) 22
(B) 77
(C) 26
(D) 41
(E) 66
a: Stream of consciousness: (1 man + 1 woman)'s 1 day work = (1/3 + 1/4) = 7/12 Work done by 1 man and 1 woman in 1/4 day = (7/12 * 1/4) = 7/48
Remaining work = (1 - 7/48) = 41/48
Work done by 1 boy in 1/4 day = ( 1/12 * 1/4) = 1/48
Number of boys required = 41/48 * 41 = 41. The answer is (D).
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q: A motorcyclist goes from Nagpur to Pune, a distance of 500 kms at an average of 100 kmph speed. Another man starts from Nagpur by car 3 Â½ hours after the first, and reaches Pune Â½ hour earlier. What is the ratio of the speed of the motorcycle and the car?
Options:
(A) 1:2
(B) 1:7
(C) 3:5
(D) 1:5
(E) 1:1
a: Stream of consciousness: T = 500/100 = 10 h
T = 10 - 4 = 6
Time Ratio = 10:6 = 5:3
Speed Ratio = 3:5 The answer is (C).
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q: If a and b are unique prime integers, which of the following must be odd?
Options:
(A) a−b
(B) 2a+2b
(C) 2a−2b
(D) 2a / 2b
(E) ab^2
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
Stream of consciousness: Any number multiplied by 2 has to be an even number. hence The answer is (A).
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