question: Look at this series: 21, 9, 21, 11, 21, 13, 21, ... What number should come next?
Options:
(A) 15
(B) 14
(C) 17
(D) 18
(E) 19
answer: Stream of consciousness: In this alternating repetition series, the random number 21 is interpolated every other number into an otherwise simple addition series that increases by 2, beginning with the number 9. The answer is (A).

q: There are seven thieves. They stole diamonds from a diamond merchant and ran away. While running, night sets in and they decide to rest in the jungle.
When everybody was sleeping, two of them woke up and decided to divide the diamonds equally among themselves. But when they divided the diamonds equally, one diamond is left.
So they woke up the 3rd thief and tried to divide the diamonds equally again but still one diamond was left. Then they woke up the 4th thief to divide the diamonds equally again, and again one diamond was left. This happened with the 5th and 6th thief one diamond was still left.
Finally, they woke up the 7th thief and this time the diamonds were divided equally.
How many diamonds did they steal in total?
Options:
(A) 700
(B) 721
(C) 702
(D) 703
(E) None of the above
a: Stream of consciousness: We need a number that is a multiple of 7 that will give a remainder of 1 when divided by 2, 3, 4, 5, and 6. The least common multiple of these numbers is 60. So, we need a multiple of 7 that is 1 greater than a multiple of 60. The answer is (B).

question: 3 candidates in an election and received 1136, 7636 and 11628 votes respectively. What % of the total votes did the winningcandidate got in that election?
Options:
(A) 45%
(B) 56%
(C) 57%
(D) 70%
(E) 72%
answer: Stream of consciousness: Total number of votes polled = (1136 + 7636 + 11628) = 20400
So, Required percentage = 11628/20400 * 100 = 57% The answer is (C).

q: Two pipes A and B can fill a cistern in 20 and 30 minutes respectively, and a third pipe C can empty it in 50 minutes. How long will it take to fill the cistern if all the three are opened at the same time?
Options:
(A) 17 1/4 min
(B) 28 1/7 min
(C) 17 1/7 min
(D) 17 1/8 min
(E) 15 15/19 min
a: Stream of consciousness: 1/20 + 1/30 - 1/50 = 19/300
300/19 = 15 15/19 The answer is (E).

question: A pipe can fill a cistern in 20 minutes whereas the cistern when fill can be emptied by a leak in 28 minutes. When both pipes are opened, find when the cistern will be full?
Options:
(A) 17 minutes
(B) 87 minutes
(C) 70 minutes
(D) 27 minutes
(E) 11 minutes
answer: Stream of consciousness: 1/20 - 1/28 = 1/70
70 minutes The answer is (C).

question: What is the are of an equilateral triangle of side 8 cm?
Options:
(A) 645
(B) 649
(C) 163
(D) 643
(E) 642
answer:
Stream of consciousness: Area of an equilateral triangle = 3/4 S2
If S = 8, Area of triangle = 3/4 * 8 * 8 = 163 cm2; The answer is (C).