Se noteazaa lungimea drumului cu x.
Etape Rest
i)x/4+6 x-x/4-6=3x/4-6
ii)1/3*(3x/4-6)+4=x/4+2 3x/4-6-x/4-2=x/2-8
iii)1/2*(x/2-8)+10=x/4+6
iv)42 km
Vom avea deci:
x/4+6+x/4+2+x/4+6+42=x
3x/4+56=x |*4
3x+224=4x
x=224 km (lungimea drumului)
In prima etapa:224/4+6=62 km
In a doua etapa: 224/4+4=60 km
In a treia etapa: 224/4+6=62 km
In a patra etapa : 42 km