question: A train 310 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
Options:
(A) 40 sec
(B) 50 sec
(C) 44 sec
(D) 36 sec
(E) 60 sec
answer: Stream of consciousness: Speed = 45 * 5/18 = 25/2 m/sec
Total distance covered = 310 + 140 = 450 m
Required time = 450 * 2/25 = 36 sec The answer is (D).


q: Henry earns $120 a week from his job. His income increased and now makes $180 a week. What is the percent increase?
Options:
(A) 70%
(B) 60%
(C) 50%
(D) 40%
(E) 30%
a: Stream of consciousness: Increase = (60/120)*100 = (1/2)*100 = 50%. The answer is (C).


question: Which of the following numbers is divisible by 9?
Options:
(A) 23274
(B) 25181
(C) 31001
(D) 50123
(E) 11251
answer: Stream of consciousness: 23274. This is the only option with last two digits divisible by 9 The answer is (A).


q: By how much is 50% of 250 greater than 25% of 400.
Options:
(A) 25
(B) 26
(C) 29
(D) 39
(E) 26
a: Stream of consciousness: (50/100) * 250 â€“ (25/100) * 400
125 - 100 = 25 The answer is (B).


question: The average age of a class of 32 students is 16 yrs. if the teacher's age is also included, the average increases by one year. Find the age of the teacher
Options:
(A) 34 Years
(B) 37 Years
(C) 49 Years
(D) 51 Years
(E) 57 Years
answer: Stream of consciousness: Total age of students is 32X16 = 512 Years
Total age inclusive of teacher = 33X (16+1) = 561
So, Teacher's age is 561-512 = 49 Yrs
There is a shortcut for these type of problems
Teacher's age is 16+(33X1) = 49 Years The answer is (C).


question: A person spends 1/3rd of the money with him on clothes, 1/5th of the remaining on food and 1/4th of the remaining on travel. Now, he is left with Rs 200. How much did he have with him in the beginning?
Options:
(A) s 200
(B) s 500
(C) s 300
(D) s 450
(E) s 550
answer:
Stream of consciousness: Suppose the amount in the beginning was Rs ’x’
Money spent on clothes = Rs 1x/3 Balance = Rs 2x/3
Money spent on food = 1/5 of 2x/3 = Rs 2x/15
Balance = 2x/3 - 2x/15 = Rs 8x/15
Money spent on travel = 1/4 of 8x/15 = Rs 2x/15 = 8x/15 - 2x/15 = 6x/15 = Rs2x/5
Therefore 2x/5 = 200 = 500 The answer is (B).