Răspuns :
a+b=72 |____|a
a=b:5 |____|____|____|_____|_____|
72:6=12
a=12
b=12x5
b=60
verificare 60+12=70
a=b:5 |____|____|____|_____|_____|
72:6=12
a=12
b=12x5
b=60
verificare 60+12=70