Quantitative Aptitude - Arithmetic Ability Questions

Let the present ages of Kapil and Avanthi be K & A

Given difference in their ages = K - A = 9 years ...........(1)

After 7 years, K + 7 =  2(A + 7) ......(2)

K + 7 = 2A + 14

K - 2A = 7 ............(3)

K - A = 9 ....(1)

From (1) & (3),

-A = -2

=> A = 2 years

=> K = 9 + 2 = 11 years

Required, age of Kapil after 4 years = 11 + 4 = 15 years.

M=P(1+i)^n

I=M-P

From the given data,

let the length, breadth and height of the cuboid are m, n, r

m x n = 12

n x r = 20

r x m = 15

Hence, m x n x n x r x r x m = 12 x 20 x 15

mnr = sqrt of (12x20x15) = 60 cub.cm.

Let the distance between A and B = D

Given the speed of maruthi = 60 kmph

Maruthi reaches from A to B in 6 hrs 20 min = 6 + 20/60 = 6 1/3 hrs

Now, the distance between A & B = D = speed x time = 60 x 19/3 = 380 kms

As the distance is same for toyato also,

given time for toyato = 4 hrs 45 min = 4 + 45/60 = 4 3/4 = 19/4 hrs

speed of toyato = distance/time = 380/19/4 = 380 x 4/19 = 80 kmph.

(3x + 2) (2x - 5) = ax2+kx+n ...............(1)

But (3x + 2)(2x - 5) = 6x2-11x-10........(2)

so by comparing (1) & (2),

we get a= 6, k= -11 , n= -10

(a - n + k) = 6 + 10 - 11 = 5.

C.P of article = 6500 * (100/80) = Rs. 8125 S.P for a gain of 20% = (8125*120)/100 = Rs. 9750

We know that,

I = PTR/100

ATQ,

15800 = 14800 x T x 6/100

T = 15800/148x7

T = 15800/1036

T = 15.25 yrs.