question: A train 650 m long is running at a speed of 117 km/hr. In what time will it pass a bridge 325 m long?
Options:
(A) 30
(B) 35
(C) 40
(D) 45
(E) 50
answer: Stream of consciousness: Speed = 117 * 5/18 = 65/2 m/sec
Total distance covered = 650 + 325 = 975 m
Required time = 975 * 2/65 = 30 sec The answer is (A).


q: A train 250 m long running at 72 kmph crosses a platform in 25 sec. What is the length of the platform?
Options:
(A) 150m
(B) 200m
(C) 250m
(D) 270m
(E) 300 m
a: Stream of consciousness: D = 72 * 5/18 = 25 = 500 – 250 = 250m The answer is (C).


question: What is the least number should be added to 1056, so the sum of the number is completely divisible by 26?
Options:
(A) 10
(B) 20
(C) 30
(D) 40
(E) 50
answer: Stream of consciousness: (1056 / 26) gives remainder 16
10 + 16 = 26, So we need to add 10 The answer is (A).


q: In a jar there are 3 golf balls and 2 ping pong balls. What is the probability of drawing at least one golf ball when drawing two consecutive balls randomly?
Options:
(A) 1/4
(B) 1/2
(C) 3/5
(D) 9/10
(E) 16/20
a: Stream of consciousness: P(at least one gold ball) = 1 - P(no golf ball, so 2 ping pong balls) = 1- 2/5*1/4 = 9/10. The answer is (D).


question: The average of nine numbers is 15. The average of first four numbers is 11 and the average of last four numbers is 14. What is the middle number?
Options:
(A) 19
(B) 20
(C) 35
(D) 31
(E) 27
answer: Stream of consciousness: The total of nine numbers = 9X15 = 135
The total of first 4 and last 4 numbers is = 4 X 11+4 X 14 = 100
So, the middle number is (135 - 100 ) = 35 The answer is (C).


question: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 30 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 60 minutes
(D) 27 minutes
(E) 11 minutes
answer:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Stream of consciousness: 1/20 - 1/30 = 1/60
60 minutes The answer is (C).