There are 3 members in a family. The average age of the father and mother is 40 years. The average age of the father, mother and daughter is 30 years. Find the age (in years) of the daughter.

If 5 times a son's age is added to his father's age, the sum is 42 years. If 2.8 times the father's age is added to the son's age, the sum is 76 years. What is the father's age (in years)?

The average age of 28 students of a class is 40 years. If the age of the teacher is also included, the average age of the whole group becomes 41 years. The age (in years) of the teacher is:

The sum of the ages of three friends is 188 years. What was the sum of their ages 10 years ago?

Six times the present age of P exceeds the present age of Q by 46 years. After 10 years, six times Q’s age will be 18 years less than five times P’s age at that time. What is the present age of Q (in years)?​

Three times the present age of P exceeds the present age of Q by 23 years. After 7 years, six times Q’s age will be 30 years less than six times P’s age at that time. What is the present age (in years) of Q?

The present ages of A and B are in the ratio 4 : 3 respectively. Three years ago, the ratio of their ages was 7 : 5. Find the age of A after 4 years from now (in years).

If 5 times a son’s age is added to his father’s age, the sum is 79 years. If 2.5 times the father’s age is added to the son’s age, the sum is 94 years. What is the father’s age (in years)?

If 2 times Mary's present age is 27 years more than 5 times Dia's present age, and 7 times Dia's present age is 9 years less than Mary's present age, then what is the difference (in years) between the ages of Mary and Dia?

3 years ago, a father's age was 24 years more than twice his son's age. After how many years from now will his age be twice his son's age?

Seven years ago, the sum of the ages of a mother and her daughter was 46 years. The ratio of their present ages is 3 : 1. What is the present age of the daughter ?