Final answer:
The unit rate of this proportional relationship is 60 bikes per hour.
Step-by-step explanation:
The unit rate of this proportional relationship can be found by dividing the number of bikes produced by the number of hours it takes. In this case, the machine produces 300 bikes every 5 hours.
Dividing the bikes produced (300) by the number of hours (5), we get a unit rate of 60 bikes per hour. This means that the machine produces 60 bikes every hour.
The unit rate is important because it tells us how much of something is produced or consumed in a given amount of time, in this case, the number of bikes produced per hour.