Answer :
Rate of 3 every 10 minutes.
In 10 minutes there are 3 buses.
In 1 minute it is (3/10). For 1 hour = 60 minutes.
For 60 minutes = 3/10 * 60 = 18.
18 buses.
In 10 minutes there are 3 buses.
In 1 minute it is (3/10). For 1 hour = 60 minutes.
For 60 minutes = 3/10 * 60 = 18.
18 buses.