Q: A train 560 m in length crosses a telegraph post in 16 seconds. The speed of the train is?
Options:
(A) 126 kmph
(B) 77 kmph
(C) 54 kmph
(D) 71 kmph
(E) 88 kmph
A: OK... Stream of consciousness: S = 560/16 * 18/5 = 126 kmph
The answer is (A).

Q: An enterprising businessman earns an income of Re 1 on the first day of his business. On every subsequent day, he earns an income which is just double of that made on the previous day. On the 20th day of business, he earns an income of:
Options:
(A) Rs 219
(B) Rs 220
(C) Rs 20
(D) Rs 20
(E) Rs 30
A: OK... Stream of consciousness: 2nd day he earns = 2 = 2(2 1)
3rd day he earns = 2(3 1)
On 20th day he earns 2(20 -1) = 219 rupees
The answer is (A).

Q: X can finish a work in 20 days. Y can finish the same work in 15 days. Yworked for 9 days and left the job. how many days does X alone need to finish the remaining work?
Options:
(A) 3
(B) 5
(C) 6
(D) 8
(E) 9
A: OK... Stream of consciousness: Work done by X in 1 day = 1/20
Work done by Y in 1 day = 1/15
Work done by Y in 9 days = 9/15 = 3/5
Remaining work = 1 3/5 = 2/5
Number of days in which X can finish the remaining work = (2/5) / (1/20) = 8
The answer is (D).

Q: Find the mean proportional between 64 & 81?
Options:
(A) A) 59
(B) B) 61
(C) C) 63
(D) D) 72
(E) E) 67
A:
OK... Stream of consciousness: Formula = ab
A = 64 and B = 81
6481 = 8 9 = 72
The answer is (D).