Q: Thirty percent of Country Y's yearly exports come from fruit exports. One-sixth of all fruit exports from Country Y are orange exports. If country Y generates $50 million from its orange exports, how much money does it generate from its yearly total of exports?
Options:
(A) $1000m
(B) $25.5m
(C) $106.25m
(D) $127.5m
(E) $153m
A: OK... Stream of consciousness: 30/100*1/6*(total) = 50
1/20*(total) = 50
(total) = 50*20 = 1000
The answer is (A).

Q: 10 books are placed at random in a shelf. The probability that a pair of books will always be together is
Options:
(A) 1/10
(B) 9/10
(C) 1/5
(D) 3/10
(E) 1/2
A: OK... Stream of consciousness: 10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!
Required probability = 1/5
The answer is (C).

Q: A train 250 m long, running with a speed of 50 km/hr will pass a tree in?
Options:
(A) 18sec
(B) 20sec
(C) 25sec
(D) 30sec
(E) 1min
A: OK... Stream of consciousness: Speed = 50 * 5/18 = 125/9 m/sec
Time taken = 250 *9/125 = 18 sec
The answer is (A).

Q: If x is a positive integer, which of the following could NOT be the square of x?
Options:
(A) 5,008,644
(B) 5,004,169
(C) 4,999,696
(D) 4,995,225
(E) 4,990,752
A:
OK... Stream of consciousness: A perfect square will never end in 2, 3, 7 or 8. (last digit cannot be 2, 3, 7 or 8)
Here E is the odd one out.
The answer is (E).