The ratio of the present age of father to that of son is 7:2. After 10 years their ages will be in the ratio of 9:4. The present ages of the father is
Answers
Solution
Given :-
- Ratio of age of father and son = 7:2
- After 10 years there age will be in ratio = 9:4
Find :-
- present Age of Father & Son
Explanation
Let,
- Age of father = x years
- Age of Son = y years
A/C to question
(Ratio of age of father and son = 7:2 )
==> x : y = 7:2
==> x/y = 7/2
==> 2x - 7y = 0 -------(1)
Again,
==> ( x +10):(y+10) = 9:4
==> (x+10)/(y+10) = 9/4
==> 4x + 40 = 9y + 90
==> 4x - 9y = 90-40
==> 4x - 9y = 50 ---------(2)
Multiply by 2 in equ(1)
==> 4x - 14y = 0 ----------(3)
Subtract equ(2) & equ(3)
==> -9y + 14y = 50
==> 5y = 50
==> y = 50/5
==> y = 10
Keep Value of y in equ(1)
==> 2x - 7*10 = 0
==> 2x = 70
==>x = 70/2
==>x = 35
Hence
- Present Age of Father = 35 years
- Present Age of Son = 10 years
__________________
Age of father = x years
Age of Son = y years
==> x : y = 7:2
==> x/y = 7/2
==> 2x - 7y = 0 -------(1)
==> ( x +10):(y+10) = 9:4
==> (x+10)/(y+10) = 9/4
==> 4x + 40 = 9y + 90
==> 4x - 9y = 90-40
==> 4x - 9y = 50 ---------(2)
==> 4x - 14y = 0 ----------(3)
==> -9y + 14y = 50
==> 5y = 50
==> y = 50/5
==> y = 10
==> 2x - 7*10 = 0
==> 2x = 70
==>x = 70/2
==>x = 35
Hence
Present Age of Father = 35 years
Present Age of Son = 10 years