This holiday weekend, Dave is going to Chicago to shop and see a baseball game. To avoid traffic, Dave decides to take the train. There is a proportional relationship between the time (in minutes) Dave spends riding the train, x, and the distance he travels (in miles), y. x (minutes) y (miles) 8 8 10 10 13 13 14 14 What is the constant of proportionality? Write your answer as a whole number or decimal. miles per minute