question: If rupee one produces rupees nine over a period of 40 years, find the rate of simple interest?
Options:
(A) 22 1/7%
(B) 22 7/2%
(C) 29 1/2%
(D) 22 1/2%
(E) 22 1/3%
answer: Stream of consciousness: 9 = (1*40*R)/100
R = 22 1/2 % The answer is (D).

q: In what time a sum of money double itself at 7% per annum simple interest?
Options:
(A) 33 1/8%
(B) 33 1/3%
(C) 14 2/7%
(D) 32 1/3%
(E) 23 1/3%
a: Stream of consciousness: P = (P*7*R)/100
R = 14 2/7% The answer is (C).

question: Ravi can do a piece of work in 50 days while Prakash can do it in 75 days. In how many days will they finish it together?
Options:
(A) 30 days
(B) 35 days
(C) 25 days
(D) 27 days
(E) 29 days
answer: Stream of consciousness: 1/50 + 1/75 = 5/150
30/1 = 30 days The answer is (A).

q: 4000 was divided into two parts such a way that when first part was invested at 3% and the second at 5%, the whole annual interest from both the investments is Rs.144, how much was put at 3%?
Options:
(A) 3377
(B) 2678
(C) 2800
(D) 2786
(E) 1981
a: Stream of consciousness: (x*3*1)/100 + [(4000 - x)*5*1]/100 = 144
3x/100 + 200 5x/100 = 144
2x/100 = 56 e x = 2800' The answer is (C).

question: A box contains nine bulbs out of which 4 are defective. If four bulbs are chosen at random, find the probability that all the four bulbs are defective.
Options:
(A) 62/63
(B) 125/126
(C) 1/63
(D) 1/42
(E) 1/126
answer: Stream of consciousness: Answer: Option E
Out of nine, five are good and four are defective. Required probability = c/c = 1/126 The answer is (E).

question: In a school of 850 boys, 46% of Muslims, 28% Hindus, 10% Sikhs and the remaining of other communities. How many belonged to the other communities?
Options:
(A) A) 136
(B) B) 627
(C) C) 153
(D) D) 721
(E) E) 159
answer:
Stream of consciousness: 46 + 28 + 10 = 84%
100 84 = 16%
850 * 16/100 = 136 The answer is (A).