9:7 Ratios are always simplified so by dividing both 18 and 14 by 2 you get 9 and seven. Because yellow triangles is stated first the 9 is put before the 7 blue triangles.
Bryce's unit rate in miles around the track is 3 rate per mile . Now, as we know the formula for speed i.e. So, Bryce's unit rate in miles around the track is 3 rate per mile .