q: A train running at the speed of 60 km/hr crosses a pole in 12 sec. What is the length of the train?
Options:
(A) 356
(B) 200
(C) 127
(D) 279
(E) 150
a: Stream of consciousness: Speed = 60 * 5/18 = 50/3 m/sec
Length of the train = speed * time = 50/3 * 12 = 200 m The answer is (B).

question: If six persons sit in a row, then the probability that three particular persons are always together is -.
Options:
(A) 1/5
(B) 1/7
(C) 1/9
(D) 1/2
(E) 2/7
answer: Stream of consciousness: 3!4! Required probability = 3!4!/6! = 1/5 The answer is (A).

q: Alice, Benjamin, and Carol each try independently to win a carnival game. If their individual probabilities for success are 2/5, 3/8, and 2/7, respectively, what is the probability that exactly two of the three players will win but one will lose?
Options:
(A) 3/140
(B) 1/280
(C) 3/280
(D) 4/56
(E) 77/280
a: Stream of consciousness: P = P(A wins, B wins, C loses) + P(A wins, B loses, C wins) + P(A loses, B wins, C wins) = 2/5*3/8*5/7 + 2/5*5/8*2/7 + 3/5*3/8*2/7 = 77/280. The answer is (E).

question: Which value of x does statisfy the inequality 2x2 + x 3 < 0?
Options:
(A) -32 < x < 1
(B) -1 < x < 32
(C) x > 1
(D) x < -25
(E) None of these
answer: Stream of consciousness: 2x2 + x 3 < 0
(x 1)(2x + 3) < 0 or, -32 < x < 1 The answer is (A).

q: 85 white and black tiles will be used to form a 10x10 square pattern. If there must be at least one black tile in every row and at least one white tile in every column, what is the maximum difference between the number of black and white tiles that can be used?
Options:
(A) 75
(B) 80
(C) 85
(D) 90
(E) 95
a: Stream of consciousness: Answer = A
Please refer diagram below
85 - 10 = 75 The answer is (A).

q: There are 20 balls in a jar. You take out 2 blue balls without putting them back inside, and now the probability of pulling out a blue ball is 1/5. How many blue balls were there in the beginning?
Options:
(A) 12.
(B) 9.
(C) 8.
(D) 7.
(E) 6.
a:
Stream of consciousness: 12 = 3 blue balls + 18 / 2 The answer is (A).