a : b = 5 rest 24
a = 5×b+24
c = a : 2 = (5×b+24) : 2
a+b+c = 257
inlocuim in ecuatie in functie de b
5×b+24 + b + (5×b+24) : 2 = 257
6×b + 24 + (5×b+24) : 2 = 257 |×2
12×b+ 48 + 5×b +24 = 514
17×b = 514 - 72
17×b = 442
b = 442 : 17
b = 26
a = 5×26+24 = 130 + 24 = 154
c = 154 : 2 = 77
Verificare:
154 + 26 + 77 = 257
a = 154
b = 26
c = 77