question: If rupee one produces rupees nine over a period of 40 years, find the rate of simple interest?
Options:
(A) 22 1/9 %
(B) 22 2/2 %
(C) 23 1/2 %
(D) 22 1/2 %
(E) 62 1/2 %
answer: Stream of consciousness: 9 = (1*40*R)/100
R = 22 1/2 % The answer is (D).

q: 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 300. How much did he have with him in the beginning?
Options:
(A) s 200
(B) s 750
(C) s 300
(D) s 450
(E) s 550
a: 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 = 300 = 750 The answer is (B).

question: The average of first 10 odd numbers is?
Options:
(A) 11
(B) 10
(C) 88
(D) 176
(E) 12
answer: Stream of consciousness: Sum of 10 odd no. = 100
Average = 100/10 = 10 The answer is (B).

q: In a race with 30 runners where 3 trophies will be given to the top 5 runners (the trophies are distinct: first place, second place, etc), how many ways can this be done?
Options:
(A) 5^3 ways
(B) 8^9 ways
(C) 7^8 ways
(D) 8^7 ways
(E) 8^6 ways
a: Stream of consciousness: 5 people can be prized with 3 distinct prizes in 5^3 ways The answer is (A).

question: If a man can cover 30 metres in one second, how many kilometres can he cover in 3 hours 45 minutes?
Options:
(A) 118 km
(B) 162 km
(C) 1767 km
(D) 1887 km
(E) 405 km
answer: Stream of consciousness: 30 m/s = 30 * 18/5 kmph
3 hours 45 minutes = 3 3/4 hours = 15/4 hours
Distance = speed * time = 30 * 18/5 * 15/4 km = 405 km. The answer is (E).

question: A and B together can complete a work in 12 days. A alone can complete it in 20 days. If B does the work only for half a day daily, then in how many days A and B together will complete the work?
Options:
(A) 22
(B) 88
(C) 15
(D) 66
(E) 81
answer:
Stream of consciousness: B's 1 day work = (1/12 - 1/20) = 1/30
Now, (A + B)'s 1 day work = (1/20 + 1/60) = 1/15
So, A and B together will complete the work in 15 days. The answer is (C).