X can finish a work in 20 days. Y can finish the same work in 16 days. Y worked for 12 days and left the job. how many days does X alone need to finish the remaining work?
Options:
(A) 2
(B) 3
(C) 9
(D) 5
(E) 8

Work done by X in 1 day = 1/20
Work done by Y in 1 day = 1/16
Work done by Y in 12 days = 12/16 = 3/4
Remaining work = 1 3/4 = 1/4
Number of days in which X can finish the remaining work = (1/4) / (1/20) = 5 So the answer is: (D).

The measure of the side of a square is quadrupled. If x represents the perimeter of the original square, what is the value of the new perimeter?
Options:
(A) 3x
(B) 4x
(C) 9x
(D) 12x
(E) 27x

Original perimeter = x
Hence original side = x/4
New side = 4x/4
New perimeter = 4*4x/4 = 4x So the answer is: (B).

A 600 meter long train crosses a signal post in 40 seconds. How long will it take to cross a 3 kilometer long bridge, at the same speed?
Options:
(A) 4 min
(B) 2 min
(C) 8 min
(D) 9 min
(E) 5 min

S = 600/40 = 15 mps
S = 3600/15 = 240 sec = 4 min So the answer is: (A).

Find the product of the local value and absolute value of 4 in 20468?
Options:
(A) 1000
(B) 1100
(C) 1200
(D) 1340
(E) 1600
Local value of 4 = 4 x 100 = 400
Place value of 4 = 4
There fore = 4 x 400 = 1600 So the answer is: (E).