Metoda na krzyż.
[tex]\dfrac{a}{b}=\dfrac{c}{d}\quad= > \quad{a}d=bc[/tex]
[tex]1\mbox{ h i }15\mbox{ min}=75\mbox{ min}[/tex]
a)
[tex]9600\mbox{ m}=9,6\mbox{ km}[/tex]
[tex]\dfrac{75\mbox{ min}}{x}=\dfrac{80\mbox{ km}}{9,6\mbox{ km}}[/tex]
[tex]75\cdot9,6=x\cdot80\\720=80x\quad|:80\\9=x\\x=9\mbox{ km}[/tex]
b)
[tex]\dfrac{75\mbox{ min}}{48\mbox{ min}}=\dfrac{80\mbox{ km}}{x}[/tex]
[tex]75\cdot{x}=48\cdot80\\75x=3840\quad|:75\\x=51,2\mbox{ km}[/tex]
