EXPLANATION
As the garage is 10 centimeters wide in the drawing, and the actual wide is 5 meters, we first need to represent the centimeters in meter units.
10 centimeters ---> 0.1 meters
Now, dividing both sizes give us the scale factor:
[tex]\text{Scale factor=}\frac{0.1}{5}=\frac{1}{50}=1\colon50[/tex]The scale factor is 1:50