The rate of change is 8. This means that the number of dollars goes up by 8 for every one bushel.
Here's how you figure this out:
You want to find out if this graph is proportional. So, you always want to divide the price by the number of bushels. If all the quotients are the same, your graph is proportional. If your graph is proportional, your rate of change will be ___:1. This means that the x value will go up by the same amount for every one y value.
Example:
24:3
48:6
72:9
24 ÷ 3 = 8
48 ÷ 6 = 8
72 ÷ 9 = 8
These ratios are proportional. Our rate of change is 8:1.
