question: 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
answer: 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).


q: At 15:00 there were 21 students in the computer lab. At 15:03 and every three minutes after that, 3 students entered the lab. If at 15:10 and every ten minutes after that 8 students left the lab, how many students were in the computer lab at 15:44 ?
Options:
(A) 7
(B) 14
(C) 25
(D) 27
(E) 30
a: Stream of consciousness: Initial no of students + 3 * (1 + No of possible 3 minute intervals between 15:03 and 15:44) -
8 *(1 + No of possible 10 minute intervals between 15:10 and 15:44)
20 + 3*14 -8 * 4 = 27 The answer is (D).


question: If P(A) = 8/15, P(B) = 4/15, and P(A âˆª B) = 16/15 Find P(B|A)
Options:
(A) 1/2
(B) 2/3
(C) 3/2
(D) 2
(E) 4/7
answer: Stream of consciousness: P(B|A) = P(A âˆª B)/P(A)
P(B|A) = (16/15)/(8/15) = 2. The answer is (D).


q: A telephone company needs to create a set of 3-digit area codes. The company is entitled to use only digits 2, 4 and 8, which can be repeated. If the product of the digits in the area code must be even, how many different codes can be created?
Options:
(A) 20
(B) 22
(C) 24
(D) 27
(E) 30
a: Stream of consciousness: Total # of codes possible is 3*3*3 = 27. Oit of those 27 codes The answer is (D).


question: If rupee one produces rupees nine over a period of 42 years, find the rate of simple interest?
Options:
(A) 22 1/7 %
(B) 22 3/2 %
(C) 21 3/7 %
(D) 22 1/2 %
(E) 22 1/2 %
answer: Stream of consciousness: 9 = (1*42*R)/100
R = 21 3/7 % The answer is (C).


question: In the expression 51840/x^4, for which of the following values of x will the expression NOT be an integer?
Options:
(A) 1/2
(B) 1
(C) 2
(D) 3
(E) 5
answer:
Stream of consciousness: We can straightaway eliminate A & B, since the expression will always yields an integer for those values
Out of C, D, and E. Let us consider option E. 51840 has only one trailing zero and tens digit is not 5, so It has just one 5 in it. But for the expression to be an integer numerator should have 5^4. The answer is (E).