Question

The sum of the present ages of Ram and his son is 85 years. Five years ago, Ram was twice as old as his son. Find the present age of his son in years.

Answer 1

Let the age of Ram be x.
His son's age will be (85-x).
Five years ago,
Ram's age = x-5
His son's age = 85-x-5 = 80-x.
Now, As per the question,
2(80-x) = x-5
160-2x = x-5
3x = 165
x = 55.
So, Their ages will be 55 and 30 years respectively.

Answer 2

let the present age of ram and his son be x and y, respetively
then, x+y=85.....¡
acc to ques. five year ago the age of ram and his son x-5 = 2( y-5 )
x-5 = 2y-10 == 2y-x = 5......¡¡
now solving eqs by elimination method
y+x = 85
2y-x = 5
_________
3y = 90
y= 30
therefore, present age of son is 30