a= primul hotel
b = al doilea hotel
c= al treilea hotel
a+b+c=989 turisti
a+b= 676 turisti
b+c= 585 turisti
Adun ultimele 2 ecuatii de mai sus^ si obtin : a+ 2b+c= 676+585
a+2b+c=1260 (*)
dar cum a+b+c=989 (**)
Scad ecuatiile (*),(**) si obtin ca b = 271turisti
a + b = 676 => a = 676-271 => a = 405 turisti
b+c=584 => c = 584 - 271 => c = 313 turisti
