[tex]\displaystyle\bf\\\frac{3}{40}x=0,15\\\\\frac{3}{40}x=\frac{15^{(5}}{100}\\\\\frac{3}{40}x=\frac{^{2)}3}{~20}\\\\\frac{3}{40}x=\frac{6}{40}\\\\ x=\frac{6}{40}:\frac{3}{40}\\\\x=\frac{6}{40}\cdot\frac{40}{3}\\\\x=\frac{6\cdot40}{40\cdot3}\\\\x=\frac{6}{3}\\\\\boxed{\bf~x=2}[/tex]
