Use the graph to find the unit rate
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2.4 potatoes/pound
The unit rate is the slope of the line. The slope of the line is ...
... (change in y-value)/(change in x-value)
... = (36 potatoes - 12 potatoes)/(15 pounds - 5 pounds)
... = (24 potatoes)/(10 pounds)
... = 2.4 potatoes/pound
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The relationship here is proportional, so the line goes through the point (0, 0) and the unit rate can be figured from any point:
... (12 potates)/(5 pounds) = (24 potatoes)/(10 pounds) = (36 potatoes)/(15 pounds) = 2.4 potatoes/pound