A father is five times as old as his son, but after 15 years, he will remain only twice as old as his son. What is the age of the father?

Father is aged 3 times more than his son after 8 years, he would be two and half times of his son's age. after further 7 years, how many times would he be of his son's age?

The age of Q exceeds the age of P by 3 years. The age of R is twice the age of P and the age of Q is twice the age of S. Further, the age difference of R and S is 30 years. What is the sum of the age…

The sum of the reciprocals of A’s ages (in years) 2 years ago and 2 years from now is 2/3. The present age of A is

The sum of ages of 5 children born at the interval of 4 years each is 55 years, the age of eldest child is :

What will be the constant term in the expansion of (x + 1/x)^6?