Răspuns :
a+b+c=450
a=b+15
c:b=3 rest 15⇒c=3b+15
b+15+b+3b+15=450
5b=450-30
5b=420
b=420:5
b=84
a=84+15
a=99
c=3x84+15
c=267
Verificare : 99+84+267=450
a=b+15
c:b=3 rest 15⇒c=3b+15
b+15+b+3b+15=450
5b=450-30
5b=420
b=420:5
b=84
a=84+15
a=99
c=3x84+15
c=267
Verificare : 99+84+267=450
a+b+c=450
a=b+15
c:b=3 rest 15
c=3b+15
b+15+b+3b+15=450
5b=450-30
5b=420
a=84
b=99
c=3*84+15=252+15=267
a=b+15
c:b=3 rest 15
c=3b+15
b+15+b+3b+15=450
5b=450-30
5b=420
a=84
b=99
c=3*84+15=252+15=267