The difference between both unit rates rounded off to the nearest tenth is: 0.4 meters per second
Step-by-step explanation:
We have to calculate his unit rate for both type of races
So,
<u>Unit rate for 400m race:</u>
Distance = 400m
Time = 43 sec

<u>Unit rate for 300m Race:</u>
Distance = 300m
Time = 31 sec

The difference between both unit rates is:

Hence,
The difference between both unit rates rounded off to the nearest tenth is: 0.4 meters per second
Keywords: Unit rate, Speed
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