Question

5 years ago, rahul's age was 5 years less than three times of the sum of ages of his 3 children. After 5 years hence, his age will become 5 years more then the sum of the ages of his children. what is the present age of rahul?
A. 40 years
B. 45 years
C. 55 years
D. 50 years ​

Answer 1

Answer:

45

Step-by-step explanation:

let present age of 3children=x

let present age of Rahul=y

5years ago 3children age =x-3x5=x-15

5years AGU Rahul age=y-5

3(x-15)-5=y-5

3x-45-5=y-5

3x-y=45(1)

X+15+5=y+5

x-y=-15(2)

by subtracting 2x=60

X=30

30-y=-15

-y=-15-30=-45

y=45

Answer 2

Answer:

let Rahul present age be X

and sum of children's age be y

I.e 5 year ago

Rahul age =X-5.

3children age= y-5*3

Rahul was = 3*children ages -5

=> Rahul age =3*(y-5*3)-5

from above observation

X-5 = 3*(y-5*3)-5. =>X-5= 3y-45-5=>X-3y= -45..eq1

after 5 years

Rahul age =X+5

3Children age sum =y+5*3=y+15

simillarly

x+5=y+15+5. =>x-y=15. ...eq2

from equation 1 and 2

y=30

X=45