q: A can do a job in 18 days and B can do it in 30 days. A and B working together will finish twice the amount of work in ------- days?
Options:
(A) 22 1/8
(B) 22 1/2
(C) 22 1/1
(D) 22 1/5
(E) 22 1/9
a: Stream of consciousness: 1/18 + 1/30 = 8/90 = 4/45
45/4 = 11 *2 = 22 1/2 days The answer is (B).
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q: A motorcyclist goes from Bombay to Pune, a distance of 288 kms at an average of 32 kmph speed. Another man starts from Bombay by car 2 hours after the first, and reaches Pune hour earlier. What is the ratio of the speed of the motorcycle and the car?
Options:
(A) 1:2
(B) 1:5
(C) 1:4
(D) 2:3
(E) 1:8
a: Stream of consciousness: T = 288/32 = 9 h
T = 9 - 3 = 6
Time Ratio = 9:6 = 3:2
Speed Ratio = 2:3 The answer is (D).
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q: The speed of a boat in still water is 60kmph and the speed of the current is 10kmph. Find the speed downstream and upstream?
Options:
(A) 40, 68 kmph
(B) 70, 50 kmph
(C) 90, 60 kmph
(D) 40, 60 kmph
(E) 20, 60 kmph
a:
Stream of consciousness: Speed downstream = 60 + 10 = 70 kmph
Speed upstream = 60 - 10 = 50 kmph The answer is (B).
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