Gsmani's solution is OK, but he changed the inequality to
an equal sign.  I think you should keep the inequality
symbol < all the way to the end: 

  Let Reger's age now = x
  
  So Melanie's age 8 yrs. ago = 2x   .......  (given)
  
  Melanie's present age =  2x+8
  
  the sum of their present age = x+2x+8 < 41
 
  3x+8 < 41.   so 
    3x < 41-8 
    3x < 33
     x < 11. 
  
  So Roger's present age is no more than ll.

Edwin