Answer:
The required equation is

The value of x is 211.2 miles per hour.
Explanation:
Given : Each week, Rosario drives to an ice skating rink that is 120 miles away. The round-trip takes 2.75 hours. If he averages 55 miles per hour on his way to the rink.
To find : Equation can be used to find x, the number of miles per hour he averages on his way home?
Solution :
Firstly the distance is 120 miles.
If the average speed is 55 miles per hour.
The time taken is calculated by the formula


If the average speed is x miles per hour.

We have given that Total time taken for a trip is 2.75 hours
So, we add both the time


The required equation is

Now, we find the value of x,
Taking LCM in required equation,






Therefore, The value of x is 211.2 miles per hour.