The difference between the present ages of Lata and Smita is 84 years. Five years ago, the sum of their ages was 92 years. If Lata is older than Smita, find Smita's present age (in years).

At the time of marriage, a man was 6 years older than his wife. 12 years after the marriage, his age became 65 times the age of his wife. What were their ages (in years) at the time of marriage?

The total age of father and son at present is 40 years. After 16 years, the age of the father will be twice the age of his son. What is the present age of the son?