<PRE><B>Question 344652</B>
(supposing 5 AND 10 AND 20 shall be used), we get : 

in 5,10,20$ :
 2x5+10+4x20
 2x5+30+3x20
 2x5+50+2x20
 2x5+70+20
 
(4)
  
 4x5+2x10+3x20
 4x5+4x10+2x20
 4x5+6x10+20
 
(4+3=7)
   
 6x5+10+3x20
 6x5+30+2x20
 6x5+50+20
 
(7+3=10)
  
 8x5+2x10+2x20
 8x5+4x10+20
  
 10x5+10+2x20
 10x5+30+20
  
 12x5+2x10+20
 
(10+5=15)

 14x5+10+20

(15+1=16)

There should exist 16 ways.</PRE>