Fie X, lngimea drumului
in prima zi parcurge x/9 raman 8x/9
a doua zi parcurge 2x/9, raman x-x/9-2x/9= 2x/3
atria zi parcurge 13/24*2x/3=26x/72
deci x/9+2x/9+26x/72+55=x
x/3+26x/72+55=x
24x/72+26x/72+55=x
50x/72+55=x
55=x-50x/72
55=72x/72-50x/72
55=22x/72
5=2x/72
5=x/36
5*36=x
180=x
x=180
