question: How many two-digit numbers satisfy this property.: The last digit (unit's digit) of the square of the two-digit number is 3 ?
Options:
(A) 4
(B) 0
(C) 3
(D) 2
(E) 1
answer: Stream of consciousness: A number ending with 3 can never be a perfect square. The answer is (B).

q: The no. of girls in a class are seven times the no. of boys, which value cannever be the of total students?
Options:
(A) 10
(B) 25
(C) 30
(D) 45
(E) 50
a: Stream of consciousness: Let the boys are X, then girls are 7X, total = X+7X = 8X
So it should be multiple of 8, 30 is not a multiple of 8. The answer is (C).

question: From the set of numbers x, y, t, z and w, how many different combinations can we have without the t and z in them? Ex:. (x,y), (x), (w,y,x), etc and (x,y)=(y,x)
Options:
(A) 6
(B) 14
(C) 15
(D) 16
(E) 30
answer: Stream of consciousness: Another way: Any letter (x, y, w) can be included or not. So, we have 2^3 combinations - 2 empty combination = 6 combinations The answer is (A).

q: At what rate percent on simple interest will a sum of money double itself in 30 years?
Options:
(A) 3 1/3%
(B) 8 1/3%
(C) 3 5/3%
(D) 5 1/3%
(E) 3 1/7%
a: Stream of consciousness: P = (P*30*R)/100
R = 3 1/3% The answer is (A).

question: Amy, Bob, Cindy, and Daniel all have the same birthday, but they are all different ages. Today is their birthday. Cindy's age is divisible by Bob's age, and Amy's age is divisible by Cindy's age. If A is Amy's age in years, B is Bob's age, and C is Cindy's age, which of the following CANNOT be Daniel's age?
Options:
(A) AC/B
(B) (A+C) /B
(C) (A+B) /C
(D) AB/C
(E) (A-C) /B
answer: Stream of consciousness: Since today's is Daniel's birthday, his age must be an integer. As per the question, let A = 12, B = 2, and C = 6. Plugging these into the answer choices, only C does not yield an integer. The answer is (C).

question: The price of a T.V. set worth Rs. 20000 is to be paid in 20 installments of Rs. 1000 each. If the rate of interest be 6% per annum, and the first installment be paid at the time of purchase, then the value of the last installment covering the interest as well will be?
Options:
(A) 19002
(B) 19028
(C) 27788
(D) 19000
(E) 27711
answer:
Stream of consciousness: Money paid in cash = Rs. 1000
Balance payment = (20000 - 1000) = Rs. 19000 The answer is (D).