Q: In a class, the average age of 45 boys is 10 years and the average of 15 girls is 10 years. what is the average age of the whole class?
Options:
(A) 12 Years
(B) 12.3 Years
(C) 10 Years
(D) 13 Years
(E) 15 Years
A: OK... Stream of consciousness: Total age of 60 students
(45X 10+15 X 10) = 630
Average = 600/60 = 10 Years
The answer is (C).

Q: In how many different ways can be letters of the word SOFTWARE be arranged in such a way that the vowels always come together?
Options:
(A) 13440
(B) 1440
(C) 360
(D) 120
(E) None of these
A: OK... Stream of consciousness: When the vowels are always together, then treat all the vowels as a single letter and then all the letters can be arranged in 6! ways and also all three vowels can be arranged in 3! ways. Hence, required no. of arrangements = 6! 3! = 4320.
The answer is (E).

Q: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 40 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 40 minutes
(D) 27 minutes
(E) 11 minutes
A: OK... Stream of consciousness: 1/20 - 1/40 = 1/40
40 minutes
The answer is (C).

Q: The length Q 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%
A:
OK... Stream of consciousness: Let the length Q 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).