q: The inverse ratio of 3: 5: 1 is?
Options:
(A) 2:3:7
(B) 5:3:15
(C) 2:3:2
(D) 2:3:6
(E) 2:3:1
a: Stream of consciousness: 1/3: 1/5: 1/1 = 5:3:15 The answer is (B).

question: P and Q invested in a shop. The profits were divided in the ratio of 5: 2 respectively. If P invested Rs. 5600, the amount invested by Q is:
Options:
(A) 3500
(B) 5600
(C) 2200
(D) 2400
(E) None
answer: Stream of consciousness: Suppose Q invested Rs. y. Then, 5600/y = 5/2 or y = [5600 x 2 / 5] = 2240 The answer is (E).

q: A train 150 meters long completely crosses a 320 meters long bridge in 40 seconds. What is the speed of the train is?
Options:
(A) 32
(B) 42
(C) 54
(D) 66
(E) 09
a: Stream of consciousness: S = (150 + 320)/40 = 470/40 * 18/5 = 42 The answer is (B).

question: A train traveling at 72 kmph crosses a platform in 30 seconds and a man standing on the platform in 19 seconds. What is the length of the platform in meters?
Options:
(A) 220 meters
(B) 360 meters
(C) 420 meters
(D) 600 meters
(E) Cannot be determined
answer: Stream of consciousness: Speed of the train in metres/sec = 72000/3600 = 20
Distance travelled by train to cross the platform = 30 * 20 = 600 = Length of train + Length of platform
Distance travelled by train to cross the man = 19 * 20 = 380 = Length of train
Length of platform = 600 - 380 = 220 The answer is (A).

q: Three people took GMAT practice tests in which the minimum and maximum possible scores are 200 and 800, respectively. They each took a test 4 times, and no one scored below 450 or over 650. If the individual ranges of the three people's scores in those 4 practice tests were 30, 80 and 110, what is the difference between the maximum and minimum possible ranges of all their scores put together.
Options:
(A) 90
(B) 120
(C) 50
(D) 70
(E) 100
a: Stream of consciousness: According to the information in the question the maximum range would be between 450 and 650(200). The minimum range would be the greatest range for any one individual, which is listed in the problem as 110. So the difference between these would be 200-110 or 90. The answer is (A).

q: Two pipes A and B can fill a cistern in 20 and 30 minutes respectively, and a third pipe C can empty it in 40 minutes. How long will it take to fill the cistern if all the three are opened at the same time?
Options:
(A) 17 1/4 min
(B) 28 1/7 min
(C) 17 1/7 min
(D) 17 1/8 min
(E) 17 5/7 min
a:
Stream of consciousness: 1/20 + 1/30 - 1/40 = 7/120
120/7 = 17 1/7 The answer is (C).