Scarlet and Gunner are trying to determine which of them traveled at a greater speed when coming back from their vacation. Scarlet maintained a constant speed throughout her 7-hour journey. Her speed can be modeled by 455 = mx, where x is the time in hours, and m is the rate at which Scarlet traveled.

Based upon these two models, which person traveled at a greater speed? Explain your reasoning by using a written description of each scenario. Be sure to include the unit rates in your explanation.
Gunner's traveling time is displayed by this graph.