Q: A can do a piece of work in 9 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) 54
(E) 12
A: OK... Stream of consciousness: 8/9 + 6/x = 1
X = 54 days
The answer is (D).

Q: Find the arithmetic mean A of all roots of the following equation- see an attachment.
Options:
(A) 2
(B) 1
(C) 0.5
(D) -1/3
(E) 0.3
A: OK... Stream of consciousness: Arithmetic mean A your answer C and E are same, can you correct one of them please. thanks.
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: OK... 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).

Q: A train 250 m long running at 72 kmph crosses a platform in 50 sec. What is the length of the platform?
Options:
(A) 150m
(B) 200m
(C) 250m
(D) 750m
(E) 300 m
A:
OK... Stream of consciousness: D = 72 * 5/18 = 50 = 1000 250 = 750m
The answer is (D).