Answer :

[tex]1km\to1,000m \\\\ p\% \ of 1,000m=50m \\\\ \frac{p}{100}*1,000m=50m \\\\ p*10m=50m \\\\ \boxed{p=\frac{50m}{10m}=5}[/tex]
There are 1,000 metres in a kilometre.

50m is 1/20 of a kilometre as 50 goes into 1,000 twenty times.