Buna,:)
1.
[tex]\frac{a}{3} =\frac{b}{5} =k\\a=3k b=5k\\5-3=2k\\2k=320 k=160\\=> a=180\\b=800[/tex]
3.
[tex]\frac{a}{5} =\frac{b}{7} =k\\a=5k\\b=7k\\5k+7k=12k =>k=\frac{240}{12} \\k=20\\a=20*5=>a=100\\b=20*7=>b=140[/tex]
- Mult Succes la teme!Sper ca ti-am fost de ajutor! :)