One grandfather has three grandchildren, two of their young children age difference is 3, eldest child age is 3 times 2nd child's age and eldest child's age is two times of sum of other two children. What is the age of eldest child?

• The solution can be derived as:
  Let us assume that x is the youngest child, y is the middle one and z is the eldest child.
  As per the question,
  y-x=3.......1
  z=3y.......2
  z=2(x+y)....3
  Now, y=z/3 ....4
  x=y-3=>(z/3)-3 ......5
  
  Substitute 4 and 5 in equation 3,
  We get,
  z=2((z/3)+(z/3)-3)
  On solving,we get z=18.
  Then, x=3 and y=6.
  Thus X=3,Y=6 and Z=18. [Answer]
  
  
  
• 11 years agoHelpfull: Yes(4) No(1)