q: Find the simple interest on Rs.300 for 9 months at 6 paisa per month?
Options:
(A) 142
(B) 152
(C) 162
(D) 172
(E) 182
a: OK... I = (300*9*6)/100 = 162
The answer is (C).

q: In what time a sum of money double itself at 3% per annum simple interest?
Options:
(A) 33 1/4%
(B) 33 1/3%
(C) 33 7/3%
(D) 33 5/3%
(E) 33 1/7%
a: OK... P = (P*3*R)/100
R = 33 1/3%
The answer is (B).

q: Find the area of trapezium whose parallel sides are 20 cm and 18 cm long, and the distance between them is 15 cm.
Options:
(A) 225 cm2
(B) 275 cm2
(C) 285 cm2
(D) 315 cm2
(E) None of these
a:
OK... Area of a trapezium = 1/2 (sum of parallel sides) * (perpendicular distance between them) = 1/2 (20 + 18) * (15) = 285 cm2
The answer is (C).