Masina= 30 km
[tex]\frac{3x}{10}[/tex]
Rest:
[tex]x-\frac{3x}{10} =\frac{7x}{10}[/tex]
Motorul = 20 km
[tex]\frac{2}{7}\times \frac{7x}{10}=\frac{x}{5}[/tex]
Rest:
[tex]\frac{7x}{10}-\frac{2x}{10}=\frac{5x}{10}[/tex]
Bicicleta =30 km
[tex]\frac{3}{5} \times \frac{5x}{10} =\frac{3x}{10}[/tex]
Rest:
[tex]\frac{5x}{10}-\frac{3x}{10}=20[/tex]
2x=200
x=100 km total