question: Find the odd man out
25, 49, 81, 121, 144, 169
Options:
(A) 49
(B) 121
(C) 144
(D) 169
(E) 25
answer: Stream of consciousness: 144 is square of 12 which is even number where as all others are squares of odd numbers. The answer is (C).

q: The average age of a class of 39 students is 15 years. If the age of the teacher be included, then the average increases by 3 months .Find the age of the teacher.
Options:
(A) 22
(B) 25
(C) 8
(D) 27
(E) 19
a: Stream of consciousness: Sum of the ages of the students = 3915 = 585
New average = 15 years 3 months = 15 + 1414 year
Sum of the ages of students and teacher = 4015141514 = 40614614 = 610
Teacher age = 610 585 = 25 years. The answer is (B).

question: If in a certain sequence of consecutive multiples of 100, the median is 650, and the greatest term is 1000, how many terms that are smaller than 650 are there in the sequence?
Options:
(A) 6
(B) 4
(C) 8
(D) 12
(E) 13
answer: Stream of consciousness: Since the median is 650 we know there must be a even number of integers
So the list around 625 must go. 600 ( 650) 700 800 900 1000
Since we know there are 4 numbers greater than 650 then there must be 4 numbers less then 650. The answer is (B).

q: A can do a piece of work in 16 days. When he had worked for 2 days B joins him. If the complete work was finished in 8 days. In how many days B alone can finish the work?
Options:
(A) 18
(B) 77
(C) 66
(D) 55
(E) 12
a: Stream of consciousness: 8/16 + 6/x = 1
X = 12 days The answer is (E).

question: In a group of dogs and peacocks, the number of legs are 18 less than four times the number of heads How many peacocks are there in that group?
Options:
(A) 9
(B) 8
(C) 7
(D) 6
(E) 5
answer: Stream of consciousness: Let the number of dogs be 'x' and the number of peacocks by 'y'. Then, number of legs in the group = 4x + 2y. Number of heads in the group = x+y So, 4x+2y = 4(x+y) 18 2y = 18 y = 9 Number of peacocks in that group = 9. The answer is (A).

question: Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 6 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is?
Options:
(A) 60 gallons
(B) 100 gallons
(C) 240 gallons
(D) 180 gallons
(E) 130 gallons
answer:
Stream of consciousness: Work done by the waste pipe in 1 minute = 1/15 - (1/20 + 1/24) = - 1/40
Volume of 1/40 part = 6 gallonsVolume of whole = 6 * 40 = 240 gallons. The answer is (C).