\(\frac{2}{10}x+\frac{3}{10}x=2,5\)
\(\frac{2}{10}x+\frac{3}{10}x=\frac{5}{2}\)
\(x\cdot\left(\frac{2}{10}+\frac{3}{10}\right)=\frac{5}{2}\)
\(x\cdot\frac{1}{2}=\frac{5}{2}\)
\(x=\frac{5}{2}:\frac{1}{2}\)
\(x=\frac{5}{2}\cdot\frac{2}{1}\)
\(x=5\)
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