The father tells his son,"I was of your present age when you were born. If the father is 36 now, how old was the boy 5 years back.
1. 13
2. 15
3. 17
4. 20
13 is the answer.... Father (x) then child zero.... Now child is of x yrs then the father is of 2x yrs.... Think.... And 2x=36 thus x=18 and therefore five yrs back child is of 13yrs......