Person A: there is a proportional relationship between the amount of time and about of water used. Every 15 gallons used, the time to take a shower goes up by 5 minutes.
Person B: there is a proportional relationship between the amount of time and about of water used. Every 20 gallons used, the time to take a shower goes up by 5 minutes.
Both are linear lines in which when the gallon amount goes up, the time also goes up. Each line has a slope that never changes.
