Răspuns :
a+b+c=92
a+b=55
b+c=43
55+c=92
c=37
a+43=92
a=92-43
a=49
49+b=55
b=55-49
b=6
Verificare : 49+6+37=92
a+b=55
b+c=43
55+c=92
c=37
a+43=92
a=92-43
a=49
49+b=55
b=55-49
b=6
Verificare : 49+6+37=92
a+b+c= 92
a+b=55
b+c=43
55+c=92
c= 92-55
c= 37
b+37= 43
b= 43-37
b= 6
a+37+6=92
a+ 43 = 92
A=92-43=
A= 49