x- lungimea traseului
x/2+4 -prima zi
x-(x/2+4)=x-x/2-4=x/2-4 au ramas dupa prima zi
(x/2-4)/2 +4 =x/4-2+4=x/4+2 - a doua zi
x/2-4-x/4-2=x/4-6 - a rama dupa a treia zi
(x/4-6)/2 +4=x/8-3+4=x/8+1 - a treia zi
x-(x/2+4)-(x/4+2)-(x/8+1)=4
x-x/2-4-x/4-2-x/8-1=4
x-x/2-x/4-x/8=4+4+2+1
Aducem la acelasi numitor
8x-4x-2x-x=8*11
x=88 km