Question

The ratio of present ages of a father and a daughter is 3: 1. After 12 years, the ratio of their ages
would be 11:5. Find the present age of the Father.

Answer 1

Let the present ages be 3x and x.
After 12 years, the ages are (3x+12) and (x +12)
According to the question
(3x+12):(x+12)=11:5
5(3x+12)=11(x+12)
15x + 60 = 11x + 132
15x-11x=132-60
4x= 72
x=72/4
18
Present age of father= 18x3
=54 years

Answer 2

It is given that the ratio of present ages of a father and a daughter is 3: 1

So,
let present age of daughter be a years
And, present age of father be 3a years


According to the question :
After 12 years, the ratio of their ages will be 11 : 5.

Age of daughter after 12 years = ( a + 12 ) years
Age of father after 12 years = ( 3a + 12 ) years,

Now,
= > Ratio of father's age to daughter's age = 11 : 5

= > ( 3a + 12 ) : ( a + 12 ) = 11 : 5

= > 5( 3a + 12 ) = 11( a + 12 )

= > 15a + 60 = 11a + 132

= > 15a - 11a = 132 - 60

= > 4a = 72

= > a = 72 / 4

= > a = 18


Therefore,
present age of father = 3a years = 3( 18 ) years = 54 years


Hence, present age of father is 54 years.
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