Question 964925
let age of yougest = x
the age of middle child = x+5
the age of oldest child = 2*x

given that sum of their age = 57

so  x + (x+5) + 2*x = 57
   4*x + 5 =57
  4*x = 52
  x = 52/4
  x= 13
hence  age of youngest child = 13
       age of middle child = 13 + 5 =18
       age of oldest child = 2*13 =26