Proporcje: oblicz 5/x = 2/13 6/10 = x/20 4/7 - 8/x 3/x = 5/12 4/18 =(x+1)/30 jak to zrobic i ile to jest pomocy

[latex] frac{5}{x}= frac{2}{13} [/latex] [latex]2x=65[/latex] [latex]x=32,5[/latex] [latex] frac{6}{10}= frac{x}{20} [/latex] [latex]10x=120[/latex] [latex]x=12[/latex] [latex] frac{4}{7}= frac{8}{x} [/latex] [latex]4x=56[/latex] [latex]x=14[/latex] [latex]frac{3}{x}= frac{5}{12} [/latex] [latex]5x=36[/latex] [latex]x=7 frac{1}{5} [/latex] [latex] frac{4}{18}= frac{x+1}{30} [/latex] [latex]18(x+1)=120[/latex] [latex]18x+18=120[/latex] [latex]18x=102[/latex] [latex]x=5 frac{2}{3} [/latex]