question: A and B are integers. The expression (A+1)(B+1) is even. What can be said about A and B?
Options:
(A) They are both even numbers.
(B) At least one of them is even
(C) At least one of them is odd.
(D) They are both odd.
(E) Nothing can be said surly on A and B
answer: Stream of consciousness: Odd x Odd = Odd
Odd x Even = Even
Even x Even = Even
To fulfill condition Either (A+1) or (B+1) needs to be Even
So either A or B needs to be odd
Or At Least one of them is odd. The answer is (C).

q: There are different 5 circles. What is the number of the greatest possible points with which the circles intersect?
Options:
(A) 20
(B) 10
(C) 15
(D) 22
(E) 21
a: Stream of consciousness: Maximum points of intersection between n different circles = n*(n - 1) = 5*4 = 20 The answer is (A).

question: In filling a room with gas 100 m * 10 m * 10 m the volumes of gas will be?
Options:
(A) 100 cu.m
(B) 1000 cu.m
(C) 10000 cu.m
(D) 100000 cu.m
(E) 10000000 cu.m
answer: Stream of consciousness: 100 * 10 * 10 = 10000 The answer is (C).

q: The average age of P, Q, R, S five years ago was 45 years. By including T, the present average age of all the five is 49 years. The present age of T is?
Options:
(A) 64 years
(B) 48 years
(C) 45 years
(D) 40 years
(E) None of these
a: Stream of consciousness: Present age of P, Q, R, S = 45 x 4 + 20 = 200
Present age of P, Q, R, S and T = 49 x 5 = 245
Hence, the age of T = 245 - 200 = 45 years. The answer is (C).

question: If sushi rows 27 km upstream and 81 km down steam taking 9 hours each, then the speed of the stream
Options:
(A) 12 kmph
(B) 13 kmph
(C) 22 kmph
(D) 20 kmph
(E) 15 kmph
answer: Stream of consciousness: Speed upstream = 27/9 = 3 kmph
Speed down stream = 81/3 = 27 kmph
Speed of stream = (27-3) = 12 kmph The answer is (A).

question: The length T of a rectangle is decreased by 15% and its width is increased by 40%. Does the area of the rectangle decrease or increase and by what percent?
Options:
(A) Decreases by 19%
(B) Decreases by 25%
(C) Increases by 6%
(D) Increases by 19%
(E) Increases by 25%
answer:
Stream of consciousness: Let the length T of the rectangle be 100x, and width be 100y. Area = 100x * 100y = 10000xy
Now after the change Length = 85x, and width = 140 y. Area = 11900xy
% Change = (11900xy - 10000xy)/(10000xy) = 19 % Increase. Hence The answer is (D).