Q: A women purchased 3 towels @ Rs.100 each, 5 towels @ Rs.150 each and two towels at a certain rate which is now slipped off from his memory. But she remembers that the average price of the towels was Rs.170. Find the unknown rate of two towels?
Options:
(A) A) 400
(B) B) 650
(C) C) 500
(D) D) 550
(E) E) 600
A: OK... Stream of consciousness: 10 * 170 = 1700
3 * 100 + 5 * 150 = 1050
1700 1050 = 650
The answer is (B).

Q: In what time will a railway train 40 m long moving at the rate of 36 kmph pass a telegraph post on its way?
Options:
(A) 3 sec
(B) 4 sec
(C) 5 sec
(D) 6 sec
(E) 7 sec
A: OK... Stream of consciousness: T = 40/36 * 18/5 = 4 sec
The answer is (B).

Q: The average age of A, B and C is 25 years. If the average age of A and C is 29 years, what is the age of B in years ?
Options:
(A) 17
(B) 35
(C) 20
(D) 32
(E) 21
A: OK... Stream of consciousness: Age of B = Age of (A + B + C) Age of (A + C) = 25 3 29 2 = 75 58 = 17 years
The answer is (A).

Q: If f(x) = x^4/(x^4 - 1), what is f(1/x) in terms of f(x)?
Options:
(A) f(x)
(B) 1/-f(x)
(C) -2/-f(x)
(D) -3/-f(x)
(E) -f(x)
A:
OK... Stream of consciousness: If x = 2 then f(x) = 16/15 and f(1/x) = -16/15 which is equal to -f(x)
The answer is (E).