Solve the following

Mona's father is thrice as old as mona. After 12 years he will be just twice his daughter. find their present ages.

Solution:

Let us assume that the present age of Mona is X years, then his fathers age will be 3X years.

So the equation we get from the problem:

2(X + 12) = (3X + 12)

2X + 24 = 3X + 12

2X - 3X = 12 - 24

- X = - 12

X = 12 years.

Then Mona's present age is 12 years and her father's present age is 3 x 12 = 36 years.

Ans: 36 12 years.

  • 7

let mona's father's age be x years and her age be y years.

now, from question,

x = 3y

and after 12 years, his age will be x + 12

and his daughter's age will be y + 12

so after 12 years,

x+12 = 2(y+12) = x + 12 = 2y + 24 = x = 2y + 12

so we have 2 eq.s,

x=3y .................... (1)

and x = 2y + 12 ........................ (2)

therefore, sub. value of x from (1) in (2), we get,

3y = 2y + 12

= y = 12 years.

therefore, x = 3y = 36 years.

hence, mona is 12 years old and her father is 36 years old.

hope it helps~!

cheers!! :)

  • 1

solution:

we can consider that the present age of mona is x years.

Then her father's age will be thrice of it.

Then father's age will be 3x

Age of mona after 12 years = 12 + x years

ans: 12 years

age of her father :

12(3x )years

ans: 36 years

Therefore the age of mona is 12 yearsand her father's age is 36 years

  • 2
What are you looking for?