A father is three times as old as his son. After fifteen years the father will be twice as old as his son`s age at that time. Hence the father`s present age is
36
42
45
48
Explanation:
Let the son`s age be x, then father`s age 3x.
After 15 years:
Father`s age: 3x+15
Son`s age:x+15
Now the equation is:2(x+15) =3x+15
Solving we get x=15
Hence, father`s present is 45.