Question 778380
Let the age of the father be X and that of the son be Y.


X = 4Y _____ (1)


X+10 = 2(Y+10) _____ (2)


Substituting for X from (1) into (2)
4Y + 10 = 2Y + 20
2Y = 10
Y = 5


So, X = 4*5 = 20


So present age of father is 20 and that of son is 5.

It looks odd!!!