q: X can finish a work in 20 days. Y can finish the same work in 16 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work?
Options:
(A) 2
(B) 3
(C) 9
(D) 5
(E) 8
a: OK... Work done by X in 1 day = 1/20
Work done by Y in 1 day = 1/16
Work done by Y in 12 days = 12/16 = 3/4
Remaining work = 1 3/4 = 1/4
Number of days in which X can finish the remaining work = (1/4) / (1/20) = 5
The answer is (D).

q: Divide Rs.32000 in the ratio 1:7?
Options:
(A) 12000, 20000
(B) 12000, 200098
(C) 4000, 28000
(D) 12000, 20006
(E) 12000, 20001
a: OK... 1/8 * 32000 = 4000
7/8 * 32000 = 28000
The answer is (C).

q: Find the simple interest on Rs.500 for 9 months at 6 paisa per month?
Options:
(A) 288
(B) 270
(C) 999
(D) 278
(E) 121
a:
OK... I = (500*9*6)/100 = 270
The answer is (B).