Answer:

Where x represent the distance and t the time if we replace the info given we got:

Then the average speed for this case in m/s is 3.704 for the 200 meter race
Explanation:
The problem provides for this case the amount of distance travelled by Jessica in a given time. And we know that travels 200m in 54 seconds.
We want to find the average speed and we can use the following formula:

Where x represent the distance and t the time if we replace the info given we got:

Then the average speed for this case in m/s is 3.704 for the 200 meter race