q: A train 520 meters long is running with a speed of 34 kmph. The time taken by it to cross a tunnel 280 meters long is?
Options:
(A) 287 sec
(B) 89 sec
(C) 48 sec
(D) 16 sec
(E) 17 sec
a: Stream of consciousness: D = 580 + 280 = 800
S = 34 * 5/18 = 9 mps
T = 800/9 = 89 sec The answer is (B).

question: At what rate percent on simple interest will a sum of money double itself in 30 years?
Options:
(A) 3 1/3%
(B) 3 1/9%
(C) 3 9/3%
(D) 3 2/3%
(E) 3 6/3%
answer: Stream of consciousness: P = (P*30*R)/100
R = 3 1/3% The answer is (A).

q: Pipes A and B can fill a cistern in 8 and 24 minutes respectively. They are opened an alternate minutes. Find how many minutes, the cistern shall be full?
Options:
(A) 22
(B) 12
(C) 88
(D) 99
(E) 27
a: Stream of consciousness: 1/8 + 1/24 = 1/6
6 * 2 = 12 The answer is (B).

question: A certain number when divided by 39 leaves a remainder 20, what is the remainder when the same number is divided by 13?
Options:
(A) 11
(B) 5
(C) 8
(D) 7
(E) 9
answer: Stream of consciousness: 39 + 20 = 59/13 = 7 (Remainder) The answer is (D).

q: A train which has 390 m long, is running 45 kmph. In what time will it cross a person moving at 9 kmph in same direction ?
Options:
(A) 26 sec
(B) 39 sec
(C) 36 sec
(D) 29 sec
(E) 30 sec
a: Stream of consciousness: Time taken to cross a moving person = length of train/ relative speed
Time taken = 390/((45-9) (5/18) = 390/ 36*(5/18) = 390/10 = 39 sec The answer is (B).

q: A wheel rotates 20 times every minute and moves 15 cm during each rotation. How many metres does the wheel move in one hour?
Options:
(A) 6 metre
(B) 18 metre
(C) 180 metre
(D) 1200 metre
(E) 130 metre
a:
Stream of consciousness: Number of times wheel moves in 1 hour = 12 * 60 = 1200
:. Distance moves = (1200*15) cms = 18000 cms
In metres = 180 metre The answer is (C).