[tex] \frac{x}{1} + \frac{15x}{100} = \frac{345}{1} [/tex]
[tex]amplificam \: \frac{x}{1} \: si \: \frac{345}{1} \: cu \: 100[/tex]
[tex] \frac{x}{100} + \frac{15x}{100} = \frac{345}{100} [/tex]
[tex]100x + 15x = 34500[/tex]
[tex]115 x = 34500[/tex]
[tex]x = 34500 \div 115[/tex]
[tex]x = 300[/tex]
[tex] \frac{x}{1} - \frac{91 x}{100} = \frac{1872}{1} [/tex]
[tex]amplificam \frac{x}{1} \: si \: \frac{1872}{1} \: cu \: 100[/tex]
[tex] \frac{x}{100} - \frac{91x}{100} = \frac{1872}{100} [/tex]
[tex]100x - 91x = 187200[/tex]
[tex]9x = 187200[/tex]
[tex]x = 187200 \div 9[/tex]
[tex]x = 20800[/tex]
