Anil can do a work in 12 days while Sunil can do it in 25 days. How long will they take if both work together?
Options:
(A) 10 1/10 days
(B) 18 1/10 days
(C) 7 1/10 days
(D) 8 1/10 days
(E) 9 1/10 days

1/12 + 1/25 = 37/300
300/37 = 8 1/10 days So the answer is: (D).

The average age of a class of 32 students is 16 yrs. if the teacher's age is also included, the average increases by one year. Find the age of the teacher
Options:
(A) 34 Years
(B) 37 Years
(C) 49 Years
(D) 51 Years
(E) 57 Years

Total age of students is 32X16 = 512 Years
Total age inclusive of teacher = 33X (16+1) = 561
So, Teacher's age is 561-512 = 49 Yrs
There is a shortcut for these type of problems
Teacher's age is 16+(33X1) = 49 Years So the answer is: (C).

Find the simple interest on Rs.500 for 9 months at 6 paisa per month?
Options:
(A) 288
(B) 270
(C) 287
(D) 209
(E) 271

I = (500*9*6)/100 = 270 So the answer is: (B).

Four of the five parts numbered as (a), (b), (c), (d) and (e)in the following equations are exactly equal. You have to find out the part that is not equal to the other parts. The number of that part is the answer.
Options:
(A) a2 + 5ab + 6b2
(B) (a + 3b) (a + 2b)
(C) a(a + 3b) + 2b(a + 3b)
(D) (3a + b) (a + 2b)
(E) a(a + 2b) + 3b(a + 2b)
The other parts are equal to a2 + 5ab + 6b2. So the answer is: (D).