Răspuns :
a-b=69
a:b=3r9⇒a=3xb+9
3b+9-b=69
2b=69-9
2b=60
b=60:2
b=3
a=3x30+9
a=90+9
a=99
V:99-30=69
a:b=3r9⇒a=3xb+9
3b+9-b=69
2b=69-9
2b=60
b=60:2
b=3
a=3x30+9
a=90+9
a=99
V:99-30=69