question: There are 5 fictions and 6 non-fictions. How many cases are there such that 2 fictions and 2 non-fictions are selected from them?
Options:
(A) 90
(B) 120
(C) 150
(D) 180
(E) 200
answer: Stream of consciousness: Number of ways of selecting 2 fiction books = 5C2
Number of ways of selecting 2 non fiction books = 6C2
5C2 * 6C2 = 10 * 15 = 150 The answer is (C).

q: A no. when divided by the sum of 555 and 445 gives 2times their difference as quotient & 70 as remainder. Find the no. is?
Options:
(A) 145646
(B) 236578
(C) 645353
(D) 456546
(E) 220070
a: Stream of consciousness: (555 + 445) * 2 * 110 + 70 = 220000 + 70 = 220070 The answer is (E).

question: A can do a job in 12 days and B can do it in 15 days. A and B working together will finish twice the amount of work in days?
Options:
(A) 22 1/6
(B) 22 1/2
(C) 22 1/0
(D) 22 1/9
(E) 13 1/3
answer: Stream of consciousness: 1/12 + 1/15 = 9/60 = 3/20
20/3 = 20/3 *2 = 13 1/3 days The answer is (E).

q: An equity analyst needs to select 4 stocks for the upcoming year and rank these securities in terms of their investment potential. If the analyst has narrowed down the list of potential stocks to 8, in how many ways can she choose and rank her top 4 picks?
Options:
(A) 1200
(B) 1680
(C) 2102
(D) 4020
(E) 1840
a: Stream of consciousness: Number of ways of choosing 4 stocks = 8C4
Number of ways of ranking the chosen stocks = 4!
Hence total ways of chosing and ranking = 8C4 * 4! = 1680 The answer is (B).

question: The smallest prime number is:
Options:
(A) 1
(B) 2
(C) 3
(D) 4
(E) 5
answer: Stream of consciousness: The smallest prime number is 2. The answer is (B).

question: From among the 31 students in a class, one leader and one class representative are to be appointed. In how many ways can this be done?
Options:
(A) 1360
(B) 1260
(C) 1060
(D) 1160
(E) 930
answer:
Stream of consciousness: There are 31 students and every one has equal chance of being selected as a leader. Hence, the leader can be appointed in 31 ways. When one person is appointed as leader, we are left with 35 students. Out of these 30 teachers, we can select one class representative. So, a class representative can be selected in 30 ways. Hence, the number of ways in which a leader and class representative can be selected = 31 x 30 = 930 The answer is (E).