q: In what time a sum of money double itself at 3% per annum simple interest?
Options:
(A) 33 1/9%
(B) 33 1/3%
(C) 332 1/3%
(D) 33 9/3%
(E) 13 1/3%
a: OK... P = (P*3*R)/100
R = 33 1/3%
The answer is (B).

q: Working alone, Printers X, Y, and Z can do a certain printing job, consisting of a large number of pages, in 12, 16, and 18 hours, respectively. What is the ratio of the time it takes Printer X to do the job, working alone at its rate, to the time it takes Printers Y and Z to do the job, working together at their individual rates?
Options:
(A)  4/11
(B)  1/2
(C)  15/22
(D)  144/17
(E)  11/4
a: OK... P1 takes 12 hrs
Rate for P2P3 together = 1/16 + 1/18 = 17/144
Therefore they take 144/17
Ratio = 144/17 =
The answer is (D).

q: A train running at the speed of 180 km/hr crosses a pole in 8 seconds. Find the length of the train.
Options:
(A) 150
(B) 88
(C) 480
(D) 288
(E) 400
a:

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
OK... Speed = 180*(5/18) m/sec = 50 m/sec
Length of Train (Distance) = Speed * Time
50 *8 = 400 meter
The answer is (E).