Guillermo used the fact that a highway bus traveled 275 miles in 5 hours to find the unit rate. how can he check his answer?
a. multiply the unit rate by 5 hours and see if it equals the total distance
b. multiply the unit rate by 5 hours and see if it equals the total time
c. multiply the unit rate by 275 miles and see if it equals the total distance.
d. multiply the unit rate by 275 miles and see if it equals the total time.

Guillermo used the fact that a highway bus traveled 275 miles in 5 hours to find the unit rate. To find the unit rate, take 275/5=55 miles/hour, so a highway bus travels at a rare of 55 miles per hour.
To check if mine answer is right, I will multiply the unit rate or 55 miles per hour with 5 hours to see if that is equal to the total distance
Check:
55 miles/hour*5 hour
Cancel both of hour, so
55 miles*5=275 miles. As a result, A. multiply the unit rate by 5 hours and see if it equals the total distance is your final answer. Hope it help!

Multiply the unit rate by 5 hours and see if it equals the total distance is your final answer ; ) 

Ibelieve it would be letter c (: