There is a father, a mother and 2 sons in a family and their total age is 60 years. The difference between the sons' age is 3 years, mother's age exceeds the sum of the sons' age by 17 years and the difference of age of father and mother is equal to the age of the elder son. How old is the father?

Let sons be x and y (x > y). x - y = 3, so x = y + 3. Mother = (x + y) + 17. Father = Mother + x = (x + y + 17) + x = 2x + y + 17. Total = Father + Mother + x + y = (2x + y + 17) + (x + y + 17) + x + y = 4x + 3y + 34 = 60. Substituting y = x - 3: 4x + 3(x - 3) + 34 = 60, so 7x + 25 = 60, 7x = 35, x = 5. Father = 2(5) + (5-3) + 17 = 10 + 2 + 17 = 29.