q: 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 1/2 sec
(B) 7 1/7 sec
(C) 7 8/2 sec
(D) 7 1/9 sec
(E) 7 2/2 sec
a: 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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q: How many liters of oil at Rs.40 per liter should be mixed with 240 liters of a second variety of oil at Rs.60 per liter so as to get a mixture whose cost is Rs.52 per liter?
Options:
(A) 120
(B) 150
(C) 160
(D) 180
(E) 200
a: Stream of consciousness: 8:12 = 2:3
If 240 lrs of the 2nd variety taken then the 1st variety should be taken as 160 lr The answer is (C).
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q: Look at this series: 53, 53, 48, 48, 43, 43, ... What number should come next?
Options:
(A) A) 12
(B) B) 14
(C) C) 38
(D) D) 53
(E) E) 86
a:
Stream of consciousness: In this series, each number is repeated, then 5 is subtracted to arrive at the next number. The answer is (C).
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