x=drumul
[tex] \frac{20}{100} * x + \frac{25}{100} * (x - \frac{20}{100} *x) + 9 = x[/tex]
Simplificand fratia de mai sus obtin:
[tex] \frac{x}{5} + \frac{1}{4} (x- \frac{x}{5} ) + 9 = x[/tex]
[tex] \frac{x}{5} + \frac{x}{4} - \frac{x}{20} + 9 = x[/tex]
Aducand fractia la acelasi numitor (20) si simplificand-o, obtin:
4x+5x-x-20x=-9*20
8x-20x=-180
-12x=-180 => x=15km
In prima zi, ciclistul a parcus [tex] \frac{20}{100} * x = \frac{1}{5} *x= \frac{x}
{5} = \frac{15}{5} = 3[/tex]
