question: The average mark obtained by 22 candidates in an examination is 49. The average of the first ten is 55 while the last eleven is 40 .The marks obtained by the 11th candidate is ?
Options:
(A) 22
(B) 0
(C) 99
(D) 88
(E) 66
answer: Stream of consciousness: It is clear that 22 x 49 = 10 x 55 + K + 11 x 40 K = 88 The answer is (D).

q: A train 540 meters long is running with a speed of 54 kmph. The time taken by it to cross a tunnel 180 meters long is?
Options:
(A) 40
(B) 48
(C) 45
(D) 50
(E) 25
a: Stream of consciousness: D = 540 + 180 = 720
S = 54 * 5/18 = 15 mps
T = 720/15 = 48 sec The answer is (B).

question: The no. of girls in a class are seven times the no. of boys, which value cannever be the of total students?
Options:
(A) 3
(B) 5
(C) 8
(D) 9
(E) 11
answer: 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).

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) 25
(B) 27
(C) 29
(D) 32
(E) 34
a: 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 (B).

question: A shipment of 8 TV sets contains 6 black and white sets and 2 color sets. If 2 TV sets are to be chosen at random from this shipment, what is the probability that at least 1 of the 2 sets chosen will be a black and white set?
Options:
(A) 1/7
(B) 1/4
(C) 5/14
(D) 11/28
(E) 27/28
answer: Stream of consciousness: 2/8 * 1/7 = 2/56
1-(2/56) = 54/56 = 27/28 The answer is (E).

question: Q is a set of nine distinct prime numbers. If the sum of the integers in Q is even and the number x is a member of Q, then what is the least value that x can be?
Options:
(A) 2
(B) 3
(C) 4
(D) 5
(E) 7
answer:
Stream of consciousness: 2 + 3 + 5 + 7 +11 + 13 + 17 + 23 + 29 = 100 ( sum is even)
Least number = 2 The answer is (A).