question: A man rows his boat 75 km downstream and 45 km upstream, taking 2 1/2 hours each time. Find the speed of the stream?
Options:
(A) 5 kmph
(B) 6 kmph
(C) 9 kmph
(D) 8 kmph
(E) 1 kmph
answer: Stream of consciousness: Speed downstream = d/t = 75/(2 1/2) = 30 kmph
Speed upstream = d/t = 45/(2 1/2) = 18 kmph
The speed of the stream = (30 - 18)/2 = 6 kmph The answer is (B).
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question: Find the largest 2 digit number which is exactly divisible by 88?
Options:
(A) 88
(B) 89
(C) 99
(D) 54
(E) 90
answer: Stream of consciousness: Largest 2 digit number is 99
After doing 99 88 we get remainder 11
Hence largest 2 digit number exactly divisible by 88 = 99 - 11 = 88 The answer is (A).
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question: A train 280 m long, running with a speed of 63 km/hr will pass a tree in?
Options:
(A) 15 sec
(B) 16 sec
(C) 18 sec
(D) 20 sec
(E) 25 sec
answer: Stream of consciousness: Speed = 63 * 5/18 = 35/2 m/sec
Time taken = 280 * 2/35 = 16 sec The answer is (B).
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question: The average of first 17 even numbers is?
Options:
(A) 10
(B) 11
(C) 18
(D) 20
(E) 24
answer:
Stream of consciousness: Sum of 17 even numbers = 17 * 18 = 306
Average = 306/17 = 18 The answer is (C).
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