Problems on Ages - General Questions

4 years ago, A was 2 times as old as B. A is now 2 years older than B. What is B's present age?

The ratio of the present ages of A and B is 7 : 3. After 15 years the ratio will be 29 : 21. What is A's present age?

2 years ago, A was 4 times as old as B. A is now 42 years older than B. What is B's present age?

A father is 5 times as old as his son. After 11 years he will be 3 times as old as his son. What is the father's present age?

A father is 5 times as old as his son. After 18 years he will be 2 times as old as his son. What is the father's present age?