\[\boxed{\text{5.469.}}\]
\[1)\ 720 \cdot \frac{1}{4} = 180\ км.\]
\[2)\ 720 \cdot \frac{1}{3} = 240\ км.\]
\[3)\ 720 \cdot \frac{3}{4} = 180 \cdot 3 = 540\ км.\]
\[4)\ 720 \cdot \frac{5}{6} = 120 \cdot 5 = 600\ км.\]
\[5)\ 720 \cdot \frac{7}{9} = 80 \cdot 7 = 560\ км.\]
\[6)\ 720 \cdot \frac{11}{12} = 60 \cdot 11 = 660\ км.\]