Quantitative Aptitude - Arithmetic Ability Questions

Prime factors of 

252 = 2 x 2 x 3 x 3 x 7; 

308 = 2 x 2 x 7 x 11; 

198 = 2 x 3 x 3 x 11

Therefore LCM of 252, 308 and 198 is 2 x 2 x 3 x 3 x 7 x 11 = 4 x 9 x 77 = 2772.

Here clock-wise and anti-clockwise arrangements are same.

Hence total number of circular–permutations: 18P122*12 = 18!6*24

F = Rs. 2160

TD = Rs. 360

PW = F - TD = 2160 - 360 = Rs. 1800

True Discount is the Simple Interest on the present value for unexpired time

=>Simple Interest on Rs. 1800 for unexpired time = Rs. 360

Banker's Discount is the Simple Interest on the face value of the bill for unexpired time

= Simple Interest on Rs. 2160 for unexpired time

=(360/1800)* 2160

= (1/5) * 2160

=Rs. 432

Part filled by (A + B) in 1 minute = (1/60 + 1/40) = 1/24
Suppose the tank is filled in x minutes.
Then, x/2(1/24 + 1/40) = 1
(x/2) * (1/15) = 1 => x = 30 min.

Let the length of the train e x meter, and let the speed of train be y km/h, then

x=y+3×518×36   --------(1)   and   

x=y+6×518×30  ---------(2)

From eq (1) and (2), we get      

y = 12 km/h

Therefore,  x=(y+3)×518×36   =>  x= 150 m

Let Ben’s age now be B

Anita’s age now is A.

(A - 6) = P(B - 6)

But A is 17 and therefore 11 = P(B - 6)

11/P = B-6

(11/P) + 6 = B

Raj’s age today = 17 decades,
Hence, 5 decades back, he must be 12 years old.
Rahim must be 36 years old, Because (3×12).
5 years back Rahim must be 41 years old today. Because (36+5).