Răspuns:
a+b+c=403
a|............|
b|............|............|.............|
c|.............|............|.............|...........|.............|..........|.........|........|..........|
aflam primul numar
403:13=31 primul numar
aflam al doilea numar
31×3=93 al doilea numar
aflam al treilea numar
93×3=279 al treilea numar
v:31+93+279=403
am lucrat corect