q: Find the average of the first 25 natural numbers?
Options:
(A) 8
(B) 9
(C) 13
(D) 11
(E) 12
a: Stream of consciousness: Average of the first 'n' natural numbers = (n + 1)/2
We get (25 + 1)/2 = 13 The answer is (C).

question: How much is 35% of 40 is greater than 4/5 of 25?
Options:
(A) 29
(B) 776
(C) 66
(D) 14
(E) 99
answer: Stream of consciousness: (80/100) * 40 (4/5) * 25
35 - 20 = 14 The answer is (D).

q: 10 books are placed at random in a shelf. The probability that a pair of books will always be together is?
Options:
(A) 1/6
(B) 1/7
(C) 1/5
(D) 1/9
(E) 1/2
a: Stream of consciousness: 10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!
Required probability = 1/5 The answer is (C).

question: The average of first 10 odd numbers is?
Options:
(A) 22
(B) 10
(C) 98
(D) 66
(E) 88
answer: Stream of consciousness: Sum of 10 odd no. = 100
Average = 100/10 = 10 The answer is (B).

q: Ronald and Elan are working on an assignment. Ronald takes 6 hrs to type 32 pages on a computer, while Elan takes 5 hrs to type 40 pages. How much time will they take, working together on two different computers to type an assignment of 110 pages?
Options:
(A) 8 hrs 85 min
(B) 8 hrs 18 min
(C) 8 hrs 15 min
(D) 6 hrs 15 min
(E) 3 hrs 15 min
a: Stream of consciousness: Number of pages typed by Ronald in 1 hour = 32/6 = 16/3
Number of pages typed by Elan in 1 hour = 40/5 = 8
Number of pages typed by both in 1 hour = (16/3 + 8) = 40/3
Time taken by both to type 110 pages = (110 * 3/40) = 8 1/4 = 8 hrs 15 min The answer is (C).

q: Find the value of y from (12)^3 x 6^4 432 = y?
Options:
(A) 3452
(B) 2343
(C) 2435
(D) 2578
(E) 5184
a:
Stream of consciousness: Given Exp. = (12)3 x 64 = (12)3 x 64 = (12)2 x 62 = (72)2 = 5184
432 12 x 62 The answer is (E).