Answer:
65.8 miles per hour t is the speed at which the tractor-trailer is traveling
Step-by-step explanation:
Using the speed formula:

As per the statement:
A tractor-trailer travels 205.296 miles in 3.12 hours.
⇒Distance = 205.296 miles and Time = 3.12 hours
Substitute in above formula we have;

Simplify:
Speed = 65.8 miles per hour
Therefore, 65.8 miles per hour t is the speed at which the tractor-trailer is traveling