Q: The average of seven numbers is 18. The average of first three numbers is 14 and the average of last three numbers is 19. What is the middle number?
Options:
(A) 27
(B) 29
(C) 30
(D) 34
(E) 35
A: OK... Stream of consciousness: The total of seven numbers = 7X18 = 126
The total of first 3 and last 3 numbers is = 3 X 14+3 X 19 = 99
So, the middle number is (126 - 99 ) = 27
The answer is (A).

Q: A certain league has three divisions. The respective divisions had 10, 12 and 15 teams qualify for the playoffs. Each division held its own double-elimination tournament -- where a team is eliminated from the tournament upon losing two games -- in order to determine its champion. The four division champions then played in a single-elimination tournament -- where a team is eliminated upon losing one game -- in order to determine the overall league champion. Assuming that there were no ties and no forfeits, what is the maximum number of games that could have been played in order to determine the overall league champion?
Options:
(A) 70
(B) 72
(C) 73
(D) 78
(E) 80
A: OK... Stream of consciousness: Overall, there can be 73 minuses. Tus, it is
The answer is (C).

Q: If y is the smallest positive integer such that 3,150 multiplied by y is the square of an integer, then y must be
Options:
(A) 2
(B) 5
(C) 6
(D) 7
(E) 14
A: OK... Stream of consciousness: 3150*y = A^2
3 * 1050 * y = A^2
3*5*210*y = A^2
3*5*7*3*2*5*y = A^2
2*3^2*5^2*7*y = A^2
Concept: The factors of squared integer should occur in pair. So, the only numbers left are 2*7
Hence 14 ;
The answer is (E).

Q: A no.when divided by 221 gives a remainder 43, what remainder will beobtained by dividingthe same no.17?
Options:
(A) 2
(B) 7
(C) 9
(D) 11
(E) 15
A:
OK... Stream of consciousness: 221 + 43 = 264/17 = 9 (Remainder)
The answer is (C).