A is elder to B by years. A’s father F is twice as old as A and B is twice as old as his sister S. If the age of the father and sister differs by years, find A's age.
Step 1: Form a system of equation based on the given statement of problem
Let the present age of A is ,
The present age of B is ,
The present age of F is
The present age of S is
According to the question,
A is elder to B by years
F is twice as old as A
B is twice as old as S
The age of the father and sister differ by years
Step 2: Solve above system of equations
From equation (i) and (iii) we get
From equation (iv) we have put this value in equation (v) we get,
Put value of from equation (ii) in equation (vi)
Hence, the present age of A is years