algebra
posted by Raj .
A man is 4 times as old as his son.After 16 years he will be only twice as old as his son. find their present ages.

The father is 32 and the son is 8. In 16 years the father will be 48 and the son will be 24.

John is three times as old as Peter .In six years time John will be twice as old as Peter will be.Determine their present ages

In 16 years, Ben will be 3 times as old as he is right now.
How old is he right now? 
20 60

Let the present age of father be x and the son be y.
Now, x = 4y  (1)
After 16 years,
age of father will be x+ 16
age of son will be y +16
Therefore, x + 16 = 2( y + 16)
x + 16 = 2y + 32
x = 2y + 16
or 4y = 2y + 16 {Using equation (a)}
2y = 16
y = 8
Plugging back the value of y in equation (1), we get:
x = 4*8 = 32
Hence, the present age of father is 32 years and present age of son is 8 years