question: A motorcyclist goes from Bombay to Pune, a distance of 192 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) 1:7
(C) 1:9
(D) 1:5
(E) 1:1
answer: Stream of consciousness: T = 192/32 = 6 h
T = 6 - 3 = 3
Time Ratio = 6:3 = 2:1
Speed Ratio = 1:2 The answer is (A).
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question: The speed of a boat in still water is 80kmph and the speed of the current is 20kmph. Find the speed downstream and upstream?
Options:
(A) kmph
(B) kmph
(C) kmph
(D) kmph
(E) kmph
answer: Stream of consciousness: Speed downstream = 80 + 20 = 100 kmph
Speed upstream = 80 - 20 = 60 kmph The answer is (D).
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question: Two persons A and B can complete a piece of work in 30 days and 45 days respectively. If they work together, what part of the work will be completed in 7 days?
Options:
(A) 2/5
(B) 7/18
(C) 1/4
(D) 1/9
(E) 2/6
answer: Stream of consciousness: A's one day's work = 1/30
B's one day's work = 1/45
(A + B)'s one day's work = 1/30 + 1/45 = 1/18
The part of the work completed in 7 days = 7 (1/18) = 7/18. The answer is (B).
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question: Two trains are moving at 50 kmph and 70 kmph in opposite directions. Their lengths are 150 m and 100 m respectively. The time they will take to pass each other completely is?
Options:
(A) 7 1/6 sec
(B) 7 3/2 sec
(C) 7 1/7 sec
(D) 7 1/2 sec
(E) 3 3/2 sec
answer:
Stream of consciousness: 70 + 50 = 120 * 5/18 = 100/3 mps
D = 150 + 100 = 250 m
T = 250 * 3/100 = 15/2 = 7 1/2 sec The answer is (D).
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