a doua zi 112:5=22,4km
in primele 2 zile a parcurs: 112+22,4=134,4km
a treia zi 134,4:7=19,2km
pana acum a parcurs: 134,4+19,2=153,6km
mai are de parcurs: 256-153,6=102,4km
sau intr-un exercitiu
256-112-112·1/5-(112+112/5)·1/7=
=144-22,4-(112+22,4)/7=
=121,6-134,4/7=
=121,6-19,2=
=102,4km
Raspuns: mai are de parcurs 102,4km