12×4=48 km parcurge a patra zi
48+12=50 km parcurge a patra si a cincea zi
50×4=200km parcurge a treia zi
200+50=250 km parcurge in ultimele trei zile
250×2=500km parcurge a doua zi
250+500=750km parcurge in ultimele patru zile, adica 2/3 din drum
750×3÷2=1025 km are drumul