Quantitative Aptitude - Arithmetic Ability Questions

Let the smaller number be k.
Then, larger number = (3355 + k)
Therefore 3355 + k = (6k + 15)
‹=› 5k = 3340
‹=› k = 668.

Therefore, the smaller number k = 668 and now the larger number = 3355+668 = 4023.

Amount = P(1 + r/100)^t
Amount = 1875(1 + 4/100)^2
Amount = 1875(104/100)(104/100)
Amount = 2028

The given word HAPPYHOLI has 9 letters

These 9 letters can e arranged in 9! ways.

But here in the given word letters H & P are repeated twice each

Therefore, Number of ways these 9 letters can be arranged is 

9!2! x 2! = 9 x 8 x 7 x 6 x 5 x 4 x 32 = 90,720 ways.

We know that,  Speed = Distance/time

Let the speed of the train be = x kmph

           NORMAL SPEED                           SPEED 5 KMPH MORE

          Distance = 360 Km                         Distance =360
 
          speed    =  X Kmph                        Speed = (x+5)
 
            Time =360/X                              Time =360/(x+15)
          

For the same journey if the speed increased 10 kmph more it will take 1 hour less

Time with original speed - time with increased speed = 1

 => (360/x) - (360/x+10) =  1                               

 =>  (360(x+5)-360x)/x(x+5) =1

 =>   360X + 1800 -360X  = X(X+5)

  =>   X^2 + 5x - 1800 = 0

  X = 40 or -45

 X cannot be negetive value
                  

 X = 40 kmph.

Let the price of kerosene be x and household
consumption be y.
Expenditure = xy
New cost of kerosene = 1.1x, let new household
consumption be z.
In order to not to increase expenditure,
xy = 1.1x * a
⇒ a= 10y/ 11
⇒ consumption should decrease by = 1/11 X 100 = 9.09%