Problems on Ages Hard Level

A boy is one-fourth as old as his father. In 16 years the father will be twice as old as the boy. How old was the father when the boy was born?

Rita's age is three-fourths of her elder sister's. Six years ago their ages were in the ratio 2 : 3. How old is the elder sister now?

Twice A's age 5 years ago equals 3 times B's age 5 years from now. A is 25 years older than B. How old is B?

A is 32 and B is 26. After how many years will their ages be in the ratio 11 : 9?

A man is now 3 times as old as his son and is 28 years older than him. How many years ago was the man 5 times as old as his son?

Two persons differ in age by 10 years. Fifteen years ago the elder was twice as old as the younger. How old is the elder now?

A is 5 years older than B, and C is 2 years younger than B. The product of A's and C's ages is 228. How old is B?

A father and son are 72 years old together. Six years from now the father will be twice as old as the son. How old was the father when the son was born?

The present ages of P and Q are in the ratio 5 : 6. Seven years from now the ratio will be 6 : 7. How old was P seven years ago?

A father is now 3 times as old as his son. Five years ago he was 4 times as old. How old will the son be 5 years from now?