[tex](3+4.2:0.1):(1:0.3-213)*0.3125=(3+42):(\frac{10}3-213)*0.3125=45*(-\frac{3}{629})*\frac{3125}{10000}=-\frac{135}{629}*\frac{3125}{10000}=-\frac{421875}{6290000}=-0.06707...[/tex]
[tex]-0.06707 = 3.6\%\\x=100\%\\\\x=\frac{-0.06707*100\%}{3.6\%}=\frac{-6.707}{3.6}=-1.8631[/tex]
Odp. Ta liczba jest -1.8631