|____|..+12..|____|..+12..| km prima zi
|____|..+12..| km a doua zi
|____|..+12..|____| km a treia zi
68 km - 12 km × 4 =
68 km - 48 km =
20 km
2+1+2=5 (segmente egale)
20 km : 5 = 4 km (valoarea unui segment)
prima zi = 2×4 km + 2×12 km =
8 km + 24 km =
32 km
a doua zi = 1×4 km + 12 km =
4 km + 12 km =
16 km
a treia zi = 2×4 km + 12 km =
8 km + 12 km =
20 km
verificare:
32 km + 16 km + 20 km = 68 km