Answer :
I think that the (N+10) part is meant to throw you off if the man was 53 two years ago then now he is 55 and in five years from now he will be 60 years old
N=50 because if he was 53 two years ago that means he is 55 today and if n+10 is how he will be in 5 years and he is 55 then he will be 60. N plus 10 equals his age in 5 years which is 60 so n equals 50 because 50 plus 10 equals 60 which is how old he will be in 5 years.
