Answer:
1 : 2 cm/km or [tex]\frac{1}{2} \, \frac{cm}{km}[/tex]
One cm represents 2 km.
Explanation:
If 3 cm represents 6 km on the earth, the ratio to consider is: 3 : 6 cm/km which is the same as:
1 : 2 cm/km or [tex]\frac{1}{2} \, \frac{cm}{km}[/tex]
One cm represents 2 km.